here's a question that I haven't seen addressed on this subject yet...
are you a VanDweller, or will you all be living in a Motorhome??
At 13 years old, a girl is going to need some privacy and a space to call her own. When we had our motorhome, all 3 kids staked claim to certain places for themselves, and that worked out really well.
Seeing that your niece has just gone through a very dramatic loss, I think she'd feel comforted knowing that she was welcome to be with you...even if it's out on the road. (kids are very resilient, you know. She'll come through this.)
As for the 'home schooling', my wife and her siblings were ALL home schooled (all 14 of 'em
) and there are now 2 doctors, a guy who oversees the operations of 13 gas stations in downtown Chicago, and the CEO of an international shipping & exchange corp, to name a few. Don't let anyone tell you that home schooled kids can't keep up!
Bless you on this journey you're about to undertake. With hard work, and ALOT of compassion, your niece will make it through.
GodSpeed