XP: On purpose accidents

DD is 2.5 yo and was completely potty trained by 2 yo with just a small bout of regression 2 months after being trained. She has been nearly accident free for the better part of 6 months. We welcomed our DS in late July and braced for some regression, but until a few days ago she hadn't regressed. But now, she is seemingly having multiple on purpose accidents a week. She will both pee and poop herself (only at home), and is having bed wetting accidents. Seemingly nothing has changed in the last week, so what gives? How do you handle on purpose accidents and help her get back on track? When she regressed after she first potty trained she felt embarrassed and remorseful. This time around, she is completely aware and will warn you she is about to do it. And oddly enough she made a comment a few days ago as I was taking her to the bathroom "I have to go poo poo, and then I get candy" -- as if we are potty training her all over again. I know this has nothing to do with the candy itself because she definitely gets her fair share of sweets/treats around here. So confused. Any advice would be greatly appreciated. TIA!