What do you do if your 3-year-old refuses to use the toilet and he has gone pee and poop in the potty before but won't do it again and won't tell you when he goes in his pants or wear big boy undies?

I have the same problem my doctor said it was because of the new baby. They will go when their ready she said.

MY older sister screams at me cuz im 10 and still don't tell anyone that ive gone in my pants and her frends make fun of me but ive made her boyfrend crap his pants wut should i do tell them when i go in my pants or keep quiet plz plz plz help who Eva wrote this! im counting on u