Been having bathroom problems and lack of appetite. what could be wrong?

SOMETHING: When children revert to a previous stage of development they may have encountered something they can't deal with. That could be changes in the family, discipline difficulties, parental discord, etc. See what was going on just before this started. If unsure, a child psychiatrist maybe helpful.

LOTS: How old is the child? What has been happening in the family? Loss of pets, starting school, parental illness, etc. If you can't spot what made a roadblock in development, consult a child psychiatrist. Get some help - could be environmental and easily fixed or could be more serious. If you can't figure it out get some help. Everyone will feel better.