Yes, she is under weight. You can't see it here, but all her ribs are visible, but she is way better now compared to what she was when she first got her. Poor thing looked like she was starved.
That little dog you see her with is her new "room mate". He is a puppy, and name Babbo…or I think that's how it's spelled. Supposed to be from Disney...same with Ariel.
Ariel is a bit submissive yes, espesially that day, they had been in the park for 3 hours when I came! So I think she was a bit tired. But she is getting "tougher" every day. After she got Babbo in the house Ariel had transformed into a much more lively dog.
EDIT: Found a picture of her standing, not a great picture (was taken the day before), but at least it gives a better impression of her.