Babies are very different in how often they pee. Generally, babies wet 6-8 diapers per day when they are really young and urination gets less frequent as they start taking solids and as their bladder develop more and more. When your baby pees, is the urine a dark yellow? If it is, it could be a sign of dehydration.
Is he/she on diapers? How do you know she pees 4 times? How is her milk and liquid intake like? Would be great if you can provide abit more information. :)
Sai Raghavendar