My daughter knew to pee when she was one year old, but why did she pee standing up when she was one and a half years old? It's urgent, please come back quickly.
Generally, when the baby is about two years old, he enters the period of anal desire and has great interest in defecation, including the way of defecation. It is likely that the baby became interested in standing defecation after seeing others standing, so he took her to the ladies' room and taught her the correct way to defecate. Generally, the anal desire period will pass in about 2 months.