Knickers - rather lack of them!

So DD was 2 at the weekend and has been randomly going on the loo for a poo for several months now. We noticed in the last few weeks that when she is not wearing knickers she would take herself off to the potty. So for the week she has been dry and clean with no accidents, just takes herself to the potty when she needs to go and brings it to us when has finished (yes lovely I know)  - BUT she has had no knickers on all week!!! So today we tried her with knickers and she had an accident - seeemed to forget, I guess too like nappies.

Any suggestions on how to complete the toilet training loop and get her to wear knickers? (have gone through a LOT of skirts and dresses this week LOL!)

Put her in a kilt! Then she won't need knickers

It took Jody a while to learn that she was wearing knickers. I had to remind her constantly but eventually she understood (although she still does poos in them).
I would say just stock up on lots of knickers and pants and be patient.
Is she in a nappy at any other time apart from naps? I think that's what confused Jody a bit, we'd have her in a nappy if we went out and often for a while after we got home, but now nappies are just for sleeping in.