M.B.
A.,
Oh wow, I would say let her go at her own pace.
Not that this makes me an expert, but working in a daycare, we had 2 year olds that were just starting to walk when they transitioned. (I also learned that 2 year olds can sit and learn at a table like their older counterparts - just like in school! It is rare to find a teacher for 2-year-olds.)
I think she'll get the hang of it! She just may need a little extra time developing those muscles needed for locomotion. Soon you'll wonder - why was I worried? (or at least I hope that's what happens!)
How does PT handle this? Does her brother walk with her? (I'd like to know if this is normal or not also).
Good luck,
M.