Can i sleep train my 3 months old baby with a hernia on his belly botton?

Yes sleep train: You have a 3 month old baby with belly button hernia. You can sleep train the baby even with the hernia. Most hernias will close spontaneously. Sleep training and letting a baby cry should be ok. Watch to make sure baby doesn't become inconsolable. The hernia should be closed with surgery if the contents don't reduce or go back inside.