"The Princess is in this Castle" becoming Impossible?

[Wizzington]

In 1.12 this achievement will require you to get a female heir while having a Castle (the earliest fort building) in your capital. Later fort buildings will not count.

 

[Wizzington]

Don't you already get a Castle in your capital, or am I misremembering that particular DD?

No, capital gets +1 free fort level on top of any fort buildings (if any) built there.

 

[Wizzington]

Ah, ok. That makes sense. Is there a tech requirement for that first fortress level, or can you just build it from the start? I imagine this'll make this achievement achievable much earlier than it is right now?

Castle can be built from tech 1.

 

[Wizzington]

You can, but it requires you to not upgrade your Castle to a higher level fort.

 

[Wizzington]

If you've already got a female heir and then build a castle to put her in, will the achievement still fire? Or does it have to be get castle --> get princess --> put princess in this castle?

You won't be able to get it if you start the game with a female heir, order of heir/castle doesn't matter after that.