I have a 3 year old niece that has bad breath and gas all the time. She also complains about her tummy hurting and has a hard time with bowel movements. I have suggested her mother have her checked out by a doctor but she doesn't think the child has a serious problem. Please let me know if this could be a serious problem so I can tell her the possiblity of what it could be and why she may need to see a doctor.