Happy to use the potty but refusing to wear pants

[Pastamancer]

I bought a potty months ago for DD to get used to and she is now at a stage where she is choosing to use it. I have been letting her go at her own speed mostly and just have her running around with nothing on the bottom half. She is very good at taking herself over to the potty and using it for both wees and poos.

I am now trying to get her to wear pants as she needs to be clothed for nursery. She has Peppa pants as she, like almost every other toddler, is obsessed with Peppa. I have pants from Sainsburys and Next but whenever I put them on her she complains that they are too small. They fit her fine, I can pull the elastic out a long way so not too tight. I assume that it is just down to fitting differently to what she is used to.

I don't want to put her off wearing pants but at the same time she needs to learn. Should I just go ahead and make her wear them and put trousers over them that she can't take off herself? She will take the pants off if she can get to them.

[PostmanPatPat]

We're having the same problem with ds, doing well with the potty when naked from the waist down, but I'm struggling to get him to wear pants (even with bribery) and when I do get him to put them he takes them off quite quickly. How did you get round it pasta?