I started to train Baby to poop inside the potty when she was about 15 months. For many months, she was able to poo poo inside the potty at around the same time every morning without much fuss and problem. Recently, she has become very constipated and would only poo poo once every 2 days (which is not good coz constipation may lead to UTI). Not only is she constipated, she is also resisting to poo poo in the potty. Each time she shows signs of wanting to poo (by straining), we would rush to bring out the potty but I guess the poop sort of went back in (LOL!!) each time she sees the potty. She would also say "no, no, do wan" when we bring the potty out.
Instead, she prefers to poo poo in her diaper and she has a really weird way of straining the poop out too... as shown in pic below. I guess the hard poop is hurting her and she has to find a comfortable way of pushing the poop out LOL!!