"A motivated and powerful Dark Wizard and their followers will necessarily be more of a threat to a small magical country than a similar-sized group of nonmagi could to a large mundane one, but that is equally true in America as in Britain.  If your daughter comes to Hogwarts, she will be among other wizards who can keep her safe in the event such a threat emerges.  And not wishing to be rude myself, I don't think your sister intended her daughter to be forever cut off from her world of origin."

"She's been quite happy in the world I've been able to raise her in."

"I have no doubt you've done a splendid job with her.  But I believe she has the right to make her own choices about what world or worlds to inhabit, just as your sister made hers, and you made yours ten years ago."

Silence, from her mother.

"Not every wizard chooses to leave behind the nonmagical world altogether as soon as they come of age."

"Just - let me talk to her, first."

Footsteps approach the door; Clover swiftly moves backwards into the chair she'd put in place and picks up the book she'd laid down spine-up so she can look like she's been reading.

She marks her place and sets the book on her lap, as McGonagall enters.

"Your mother would like to speak with you in private."

She nods and emits pleasantries and returns to the living room.

Petunia pats the place next to her on the couch.

She sits.

"I understand Ms. McGonagall has already given you your Hogwarts letter," her mother says.

"Yes," she says.  "Lily was a wizard?"

"Yes, she was."  She sighs.  "I... want you to be able to choose the life you want for yourself.  But I am never going to be - altogether comfortable - with my daughter going off where my sister went, into the world that killed her."

Clover begins to consider what to say to her mother to make her okay with it, or to at least agree - what levers to pull or vulnerabilities to poke on - 

 - something tugs at her chest, at the thought of - playing her mother, like she used to play people.

It's unpleasant.  She's fairly certain things did not unpleasantly tug at her chest in this way in her past life.

But all she says is:  "I'm sorry.  But I want to go."

Her mother takes a breath, and smiles at her.  "I suppose I'll have to make my peace with that."

"Thank you."

"May I hug you?"

"Yes."

Hug.

Solemn hug.  And dehug.

"I think I would like to speak to Ms. McGonagall about preparing for Hogwarts now."

"That's entirely reasonable but I would like to say a few things about magical Britain from my point of view first, is that okay?"

"All right."

"The story I told you is that Lily got involved with people with powerful enemies," said Petunia.  "I wasn't just talking about falling in with wizards.  When we were children there was a man at Hogwarts named Albus Dumbledore.  He - "

She hesitates.

"The magical world is more dangerous than our world.  It's less politically stable - a small group of people can make life very unsafe for everyone else, a lot more easily.  Ten years ago magical Britain was at war, that's why I left with you.  Albus Dumbledore fought in that war.  And Lily - didn't fight exactly, but she helped Dumbledore in ways that made her and her family a target."

She looks at the closed door behind which Ms. McGonagall is waiting.

"I think Dumbledore would've let Lily leave the war behind if she decided she wanted to.  But I think... she got swept up, in magic, a little, in the adventure of it."

"I won't tell you what to do.  Your life has to be yours to do with what you will.  I just want you to promise to be careful about being swept up in the adventure and excitement of the magical world, and remember that you can always come home to your mother.  And in exchange I'll promise to support you in whatever kind of relationship with the magical world you choose to have."

Why is this making her feel things.  She doesn't like people being able to make her feel things.  Makes her feel a bit ill-at-ease.

(But - )

"I promise."