My 2 year old often gets a really sore red bottom. i use sudocream and it clears up. but happens often. i use pampers sensitive whips could it be them?

Maybe: If you have not changed diaper brands or wipes, then probably not. When kids are two and older, they frequently get diaper rash. Try vaseline or another ointment barrier to keep the stool and urine off of their skin. Change them quickly when they go in the diaper. Put on a thick layer of a good diaper cream, every diaper change, when they break out. Sometimes certain foods will be a cause.