Only poops standing up?!?!

Lala

My daughter is almost 3. She’s been potty trained for a few months. No peeing accidents for a long time. She has pooped on the potty multiple times. Even before potty training, she would stand straight up to poop in her diaper, never squated like most kids. Now, she will sit on the potty and pee and then go in a corner in her room and stand and poop in her undies. I think she can’t get herself to poop in the squatting position. We have a seat for the real toilet and then a little potty. I was thinking of letting her stand over the potty to poop (at east to start) but she poops with her legs together (I’ve tried to explain why it’s easier to poop with your legs open and she watches me poop more than I’d like). Any experience, thoughts? Ideas? Thanks!