My DD was 3 in October and was fully potty trained for about 2 months then one day she came to me when we were out and said she'd pooed and needed her nappy changed. I explained to her she doesn't wear nappies and she's done it in her big girl underwear. Since then she just goes in her underwear. There was no reason for her to regress. Nothing stressful or anything changing in her life. I'm having a huge problem with poos. She's doing it in her underwear at least twice a day now and will stand next to the toilet to do it. If I ask her if she is pooing or if she's done one she says no. But she always has. She doesn't seem to care if she's soiled herself even at nursery. What can I do? Just ride it out and keep changing her? I 100% don't want to put her in pull ups.