What Ophelia just did, with only the intent to please make her mother understand and shut up for once in her life, wasn't a compulsion-spell, or indeed any recognized spell at all.  It most strongly resembles the field of legilimency, albeit in a different, simultaneously more overt and more subtle, form.

She drew a connection with her words, and pressed it upon her mother's mind to incorporate or reject as it pleased, in a feat of stress, aptitude, and done-with-thisness that she will take quite a while to recapture with intent.

Nonetheless, Eileen Prince, for once in her life, mutters something conciliatory, though mostly unintelligible, and stops haranguing her child - because she realizes that that does in fact make sense, from within her contorted worldview.

From Ophelia's perspective, all that she can really think is '...That happened, apparently.'  She's still not out of the woods yet, though - because honestly, if she's impressed her mother, that's even more likely to make it to Tobias - 'improvised' robe-alikes from Muggle clothes and all.  So she's yet more screwed.

It is, perhaps, time to plan, so she makes her excuses and absconds upstairs.

She has a simple plan hashed out in minutes - play her sperm donor's misogyny off her mother's knowledge of wizardkind.  She'll go unnoticed beneath the argument about what masculinity is.  But...that's not really sufficient.  She has standards, and the less shouting there is, the better they're met.

Still, by the time she's fed the crows, she hasn't had any better ideas for how to dodge the blowback from this, and while she can always hope she thinks of something...

She doesn't really suspect she will come up with anything better than she already has.

And she's not going to lay her burdens on Lily.  She already does so much; it would be horrible to further impose upon her cheerfully given help, time, and kindness.

The crows are always happy to exchange shiny things and lost money (a surprisingly fruitful source of funds) for seeds, but are generally incapable of communicating how to solve complex social problems - in human, at least.

And Ophelia doesn't speak crow, so even if they knew of a good solution...she's pretty sure she couldn't understand them telling it.

Regardless...

That is a distraction from the shouting she can't find a way to avoid.  That a particularly concerned Professor could well witness, if she snuck back at the right wrong time.

She's not sure if she'd rather Professor McGonagall know.

It isn't like Severus has a choice in any of this, though - because between the shopping trip and the 1st September departure-date of the Express...

Tobias and Eileen blow up.

They always blow up.

It happens every single week.

These rows, though, are worse than usual - Eileen Prince's pride has been piqued against Tobias's disgust in magic, and neither will concede.

Ophelia can only suffer onwards, be quiet, unassuming, hidden in plain sight if she is even seen at her alleged home.  Her wand thrums softly in her clenched hand during the day; her mother's onetime wand hisses sparks of lurid green frustration as she practices late at night.  Her visits with Lily start sooner, last longer.  She buries herself in the local library often.

The crows watch, as the Seeds Person flees the Shouting People to its nest, then - starts doing something with the Stick that makes Glowy Things that it keeps in a special box, when the Shouting People are Shouting at random times.

The crows approve of the Seeds Person doing whatever the Seeds Person does with the Stick.  It means the Seeds Person is less skittish and more likely to give them seeds.  A couple of the braver members of the flock even start calling for the Seeds Person when they hear the Shouting, from near the Sometimes Wall, and that gets them seeds when the Seeds Person is done doing the thing with the Stick.  It gets them brushes, too, sometimes, which feel nice.  The crows like the Seeds Person.  The crows don't like the Shouty People.  The Shouty People aren't Shouting about anything, which is very rude of them.  They should know better.  And sometimes they throw things at crows!  That's horrible!  Really, they don't know why the Seeds Person is still nesting in this Big Hard Thing, instead of nesting in the Big Hard Thing with the Zoomy Person it seems to like.  Maybe the seeds are something it takes from the Shouty People?  The crows don't know.

The time spent with Lily, no matter that it's a desperate attempt to avoid unsolvable problems, seems to have dropped another one into her lap - and while she tries to resolve the veneer of resentment hiding Petunia Evans' deeply felt insecurity...there's not much she can do, either.  And Lily's sister already thinks Ophelia's "the worst sort of freak", for...reasons she finds inscrutable.

Why wouldn't she give her close friends pretty flowers she found?  Lily likes flowers!  She should get to have some!  And it's not like Ophelia doesn't already owe Lily a life-debt for the kindness she's shown!

Not to mention how Petunia dislikes the birds, and the birds dislike her right back.

Minerva McGonagall does not observably return to Spinner's End, but she learns some key facts over the summer all the same. There might, perhaps, have been a bespectacled cat slinking through once or twice, quiet as the grave, wearing enough stealth charms that even the crows don't notice.

She has several concerns. None of them she's willing to do crimes about, just yet, not while she's already spending a lot of her time very close to the edge of Amelia Bones' patience, but... several.

When Lily Evans is twenty, or so, she will look back on this last summer before Hogwarts and wish, desperately, that she had understood why her elder sister was so upset, and been gentler with her. 

But at this point in her life, the depth of her understanding is she's being awful because she's jealous, because we're cooler than her, so she can jump in a lake for all I care, and that's that. It's not her problem to deal with Petunia's feelings, not when she has so many more interesting things to think about. She has interesting magic textbooks and an interesting magic friend to hang out with as often as possible and a magic wand. Which, of course, she isn't using, she has plenty of time later to break the rules once she understands them better, but she carries it around with great enthusiasm, taps her fingers on it while she reads, sets it carefully on her bedside table when she sleeps, right next to the flowers. 

("That awful boy -" "You will shut up about my best friend, I'm going to learn how to put curses on you -") 

September 1st looms like a sunrise. 

Ophelia will rise to meet it, and for once dare to brave the rocks of public doubt of 'queers'; if now is not the time to bravely face the light that scours away the shadows of doubt as her true self, she does not know one better.  The clothes she selects are laid out with all the precision of her Sunday best, the night before - or, no, not just her Sunday best; she lays out her outfit, pressed crisply (thanks to focused effort and careful spellwork) and worn boldly, like a diplomat who is to deliver a long-awaited, dreadfully anticipated, declaration of war upon an enemy that outmasses her forces a hundred times or more - but that enemy will first face the project of finding her, and then a fight upon her own home ground, the land she knows as if it is herself (because it is), and she will not be found wanting in the combat that ensues.

The crows try to give her the wand that she's pretty sure is her mother's, as she sets out to Lily's place.  She tries to put it away.  They proceed to settle into a loose détente, because even as she doesn't take it, neither will the crows let her leave it, and they're smart enough to steal it from whosoever might try to make that happen.

Eileen is...

She spent the rest of the morning when she saw Severus come down the stairs in a "young girl heading to boarding school" outfit just sort of stunned, while Tobias - purpled, and then drew back at a wand - was that her wand?  Surely it couldn't be, it hasn't even been working for her for a long time now but she hasn't taken it in to get it looked over, that costs money they don't have - pointed at him, flaring a threatening light.

But if - her daughter - is brave enough to show what she's been hiding all this time, and cunning enough to prepare for the consequences, and keen enough to apparently learn how to cast even one of the simplest spells silently (because that was a Lumos, and not just wand-sparks, she's pretty sure) before she starts classes, and kind enough to inspire what little nature lives around here to loyalty, given the argument she heard her child having with the crows - then Eileen has vastly underestimated her child, and - oh, it hurts to think it, every time she even approaches the thought casting knives into her brain, and she was never one for the brave, but she's not going to drown this thought in drink and she saw someone that reminded her of her younger self, a little girl trying to face down the world, but - if this is how things are, she's hurt her child immensely in the cause of trying to give her child 'realistic expectations', and she needs to make amends.

So she'll meet the Evanses at King's Cross Station, driving five miles above the speed limit and wishing it were ten but she doesn't trust herself in Muggle cars like she would on a broom - you never forget brooms - hurriedly and harriedly wizard-dressed, and try, with all her Slytherin ambition, to be a person her daughter might someday like.

"...Daughter.  I first need to apologize, though I can't fit it in the time we have; there's too much.  I'll see if I can write.  Secondly, I'll show you where the platform is; I've been through here before and you haven't.  ...And, thirdly...  Keep - my old wand.  I - clearly need another, if it's working so eagerly for you when I can hardly make it spark.  You're -" she dabs at the corners of her eyes - "I know I've said a thousand things that aren't this, that are the opposite of this, but - you'll do great things, daughter mine, and I'm sorry I couldn't recognize how wrong I was til now."

The bird that's perched on Ophelia's shoulder preens happily as Seeds Friend takes the Make-Shouting-Go-Away stick.  She told Seeds Friend that it was hers and she should have it!  Seeds Friend shouldn't have been so stubborn!  On the other hand, now she can tell the others where Seeds Friend is going and they can all come, so maybe this is actually good?  Who knows.

Eileen Prince has been an obstacle to be avoided, like a patrolling bloodhound that a pair of clever little lady-foxes might dodge if they are very careful, for the entire time that Lily has known Ophelia. 

She is now - something else entirely, maybe.

"Oh, how nice-" begins Mr. Evans, about to step thataway and try to socialize like this is not obviously a private family moment. Lily, wincing, tugs both her parents towards platform nine, watching Eileen and Ophelia over her shoulder like a hawk. Is Ophelia okay? ... Is Eileen okay, this is a lower priority but Lily finds that suddenly she cares about that a little.

...It takes Ophelia a solid minute, to reboot, to process all that has happened in the past few minutes.

Her voice is quiet, but - sure, in a way that seems wise beyond her years.  "...I think - if the apology goes well - that - I could, can, still call you mom.  ...You should get a wand, any wand, before you go home if I can't get you to take, the ebony one, back, you know he'll be - as angry as he's ever been, possibly worse.  You need to be able to defend yourself.  So - you're coming up to the platform with me and Lily and the Evanses, okay?  And then you're going to the shops.  And if my explaining what actually happened this morning gets the Evanses to throw money at you you're taking it; I'm not going to let you choke on your pride any more than I let me do that and I don't anymore because that's stupid.  C'mon."

And now it is Ophelia tugging her adult to the group.

"Mr. and Mrs. Evans, my mother, Eileen Snape-Prince; mom," and - wow, it's a heady feeling, to be able to maybe mean that - "these are the Evanses, they've - helped me out a lot with the stuff you kind of couldn't.  And Lily's a really good friend and also a wizard, in case you hadn't guessed.  I...  Was it the breakfast table?"  She checks, Eileen nods.  "I - wasn't expecting her to show up, or be - supportive - but - now that she is - she probably needs help too, especially if she's really insisting I should keep the wand she grew up with.  Are you sure you're sure about that?"

Eileen is...still shaky, but it doesn't prevent her from trying, with muscles that almost feel like they should twinge from disuse, to smile at the people she's being introduced to.  "Yes, I'm sure -"

"Ophelia."

"Ophelia.  That's a pretty name, dear.  ...I - cannot thank you enough, Mr. and Mrs. Evans, for what you've done for her.  I...was not a responsible adult, and this morning...really drove home how badly I'd been failing, and - if she's right about you helping, I - owe you a lot.  And if there's one thing a witch like me cannot stand being, it's 'in debt'.  So - when the kids are off, we should...probably talk.  About how that could work."

She's hesitant, but...She's committed, by now, to her choice.  To trusting her daughter's choice, because somehow despite everything she's - her daughter's going to be brilliant.  She didn't take Divination, but - this thing, she knows, with the certainty of a prophecy behind it, if not the metaphysical oomph.

"But right now, we need to get the kids on the Hogwarts Express, before it fills up.  And it should be..."

She pokes her hand at the sides of a nearby pillar.  "Right through here.  Wizards-only, sorry."

The Evanses exchange somewhat awkward glances. They are at least ninety percent too English for this level of emotional vulnerability in public and also they don't actually know whether to address her as Ms. Prince or Mrs. Snape or some secret third thing.

"Erm," says Mr. Evans after a moment, "well, it's been our pleasure, of course. You're welcome to come over for tea on Sunday?"

"Oh, a hidden wall! What fun," enthuses Mrs. Evans, seizing upon the helpful distraction, "thank you for pointing us to it. I suppose you'll be going then, dear," she drapes an arm around Lily's shoulders, "you have fun at school, all right?"

"I will!!!" beams Lily. "Thanks mum thanks dad love you!" She darts between them to hug both, and then after a moment's hesitation hugs Eileen too, fleetingly. Then, before anyone can require her to explain this decision, she dashes through the wall, tugging her trunk (which can temporarily manifest wheels, when it is pretending not to be magic) behind her. 

Eileen is, frankly, also far too English for emotional vulnerability in public; it's just happening anyway, whether she likes it or not, so she's - carrying on, even if she can't keep calm about it, even if Lily choosing to trust her enough to hug her, after what must have been so much of her child's woes poured out in her ears, draws out another beading tear to dab away.

"Tea sounds like a splendid idea, Mr. Evans.  I...don't believe I know your address?  Ophelia, you'd best get going before she gets lost in there."  Her daughter is so responsible...

"You do have a point.  Thank you for the ride, Mr. and Ms. Evans."  And on to Platform Nine and Three Quarters she goes, after a polite nod to everyone that would look respectful on an adult but mostly comes off as cute on her.

Stepping through the wall is like stepping into a lake; the abrupt quiet is sharp enough to set one's ears to ringing.

Platform Nine and Three-Quarters, as ever, is full of children, and animals, and luggage. It is one of the few arguably public places in England where overt magic is not a crime. It should be a riot of laughter, and fireworks, and excitement. 

It's not.

It is, in a word, tense. No one is speaking above a whisper. Everyone is staying at least ten feet away from anyone they're not comfortable hugging. Stressed, grumbling children are being shepherded onto the train while their supervisory adults watch each other with strained, angry, frightened eyes and hands on their wands. The feeling of ambient magical hostility, of wizards wanting to do violence to each other and restraining themselves only narrowly, hangs heavy in the air. Even Lily, her enthusiasm dimming abruptly as she slows down and surveys her surroundings with concern, can tell. An untrained Legilimens like Ophelia can probably feel it nearly physically grinding against her skull like an array of hammered spikes.

No fights seem to have broken out, yet. This may perhaps be because there are several uniformed Aurors stalking the edges of the area, frowning balefully at people. Alternatively, it might be because Headmaster Albus Dumbledore himself, glowing ominously, is standing in the middle of the platform with a very grim expression on his face. Try something, it says, and find out what happened to Grindelwald.

"...Oh, gods, what, ugh...."

She can't.  She can't - there's so much she doesn't know what it is but it hurts even more than loudness -