3 year old daughter complains that her "peepee hurts". doctor visit told us nothing wrong. looks red and itchy. how can i help her?

Pee pee hurts: If you sre using bubble bath or soap suds when she takes a bath, the detergent present in the bubble bath may be irritating to her urethra causing redness and, pain and itchiness.

Ask her pediatrician: To refer to a pediatric urologist , some times urethral valves , she is born with may causing her problems

Depends on why: Soaking in a warm tub can help them relax and letting them pee into the tub can cancel out some of the discomfort. At 3 they can have a problem with bathwater soap/irritants causing some vaginal irritation which can eventually lead to a bladder infection.Avoid sudsy bathwater by using a spray attachment for bathing.Let dirty/sudsy water drain & have her soak in clean water after.