My daughter that is 6 years old has a problem with passing stool for a couple of weeks. she has to push extremely hard every week. what could the problem be?

Milk and constipatio: A common cause for constipation in the pediatric population is excessive milk/dairy consumption and insufficient fiber/veggie/fruit consumption. Once constipated, some children get into a pattern of holding poops because they are painful so it is best to get them regular. Starting with some 100% apple or pear juice can help get things going. See a doctor if vomiting, fever, painful abdomen.