My 4yr old grand-daughter can not make a bowel movement for the last 3 days she has been going in her underwear just a little like runs, but says her stomach hurts right by her belly button, but when trying to make a bowel movement she can't go. She is not eating and saying she is not hungry which that has been going on longer than three days, it's not like her not to want pizza which I bought to see if that would cheer her up, but it didn't. She took one bite and put it down. I am getting worried that the poop is stuck inside her. What could I get her? I have tried fruits, yogurts, but she just doesn't want anything. What should I do???