Mother is, they come to understand, cruel and fearsome and mighty and possessing of immense power and wealth and importance, but others covet that and try to take it from her.

Her wyrmlings, she will explain, are born to the same fate and though they must obey their mother for now one day they will have to take on the whole world themselves to mark their own territory and gather their own wealth and power.

He tries disobeying Mother sometimes but once he's old enough to understand what she wants she can just cast Suggestion at will and basically force him to do stuff. He cannot understand why anyone would want to go against that, maybe unless they were even bigger and stronger still.

One day when he is big like Mother he too will cast suggestion at will.

A Wyrmling can already dream what he will do, once he has all that power.

He's not as big as a adult dragon, yet, but nor is he a coward. The prestige and wealth and women are worth it and the pox this monster has been on his people is too much to bear and no doubt he could push to be chieftain because who'd be dumb enough to say otherwise when he walks back home carrying its head.

He’ll assemble a party of his relatives, allies and anyone with aligned interests, and reap the rewards of taking its head.

As soon as they find the thing.

The beast is invisible when it attacks and when it returns home, and you can hardly track it when it flies, but a few castings of See Invisibility can pin it down somewhat, and then all you need is a good tracker.

There's two ways into the cave, the one that can only be reached by flying and the other one that can also only be reached by flying.

What if we are all really good at climbing sheer cliff faces?

Climb is a class skill, for people like me.

Hypothetically, what happens if we're halfway up the cliff and trigger an Alarm spell?

The beast is a spellcaster too, and will have at least some kinds of defences. If she catches on too early she could burn you while you're out and exposed or Grease the rock face and watch you slip and fall or just pick up some boulders and drop them on you or -

Fly is 3rd circle, and could get one person up, or 4th circle Air Walk.

They’d have to leave a rope for everyone else, unless you know Communal Spider Climb. Everything better is beyond our abilities.

I know Fly. I give it to Trahk, or else spend a scroll of Spider Climb on our Ranger? Either way they can leave a rope for the rest of us.

I’d much rather we fight in the cave where it’s got limited space to move, then let it out into the open where it can go invisible and wait out our spells.

I can ask for Stone Shape, third circle, and seal an entrance, though the noise might alert the beast. If there’s two ways in and we don’t want her escaping, we’ll need to bring a second cleric, and hit both at the same time.

You'll probably also want a Dispel Magic, in case there's some kind of trap or warding at the entrance or a choke point, which takes up another third circle slot.

Spell slots are something casters have.
They come in different "circles" describing their relative power and complexity.
3rd means the next one after 2nd.

Three is this many fingers.

So we get up the cliff all sneaky, and then we all rush in and hit her really hard until she dies?

Then we figure out what buffs we want, so that the clerics can pray for them.

I can fit eight people in a Protection from Energy against the fire damage, that somewhat limits our party size if we want everyone under it.

We'll want to ensure everyone on the frontline can get past her damage reductions, and otherwise deal enough damage as fast as we can. We could try to prepare cold-damage attacks? But she'll might have Resist Energy herself to cover up her obvious weakness.

Since we know the beast can go invisible, we’ll want more than one countermeasure. Zarhbub can cast See Invisibility before we enter, and if we bring my wolf she could smell it out, but what after that?

She can’t attack without breaking the spell, and never attacking isn't a viable strategy so long as she's trapped. We don’t need to be too worried as long as we can hit back hard enough.

Ooh, can I be invisible too? That sounds fun.

She’ll have blindsense, and maybe See Invisibility herself, and in any regard if she attacks you first we’d be better off for it.

Let's go through the list again.

Eventually, Mother decides she's had enough of these brats.

She prepares to give them the speech.

Children, it is time for me to tell you the important things of being a dragon.

The world is vindictive and cruel to all who live in it, but as red dragons you are born to the highest caste and will come to stand above the rest. You come from a great and powerful line. Your mother, Arkrernux, is great great granddaughter of the great wyrm Daralathyxl, the most powerful dragon in all Golarion. But you can only reach his greatness if you reach his age, and that is no easy thing to do.

Survival must be your first concern.

What's a Arkrernux? What's a Daralathyxl?

They're names. Arkrernux is my name.

Do we have names?

Oh, right. She was supposed to give them names.
"Yes, you are Dergaix and Faumetun."

There, two perfectly good names.