I have a 2 year old daughter who we adopted about 7 months ago and when she sits in a chair, be it a car seat or feeding chair she does these strange kind of pull ups with her legs and arches her back slightly. She sometimes lays her head back and keeps pulling her legs up toward her chest but only raising them a few inches and she can pump like this for sometimes an hour and a half. she grabs the sides of the chair and can really go at it for awhile, tensing up her abdominal area and thighs are contracted also. Its like she s cramped up, she isn t in pain, you can tickle her for a moment and she will stop and laugh but then go right back at it again. We have tried to eliminate dairy, gluten but we aren t sure how long these foods can stay in her body. Spoke to the doctor and he hasn t seen it before but doesn t think its celiac disease as we thought it may be. Quite sure its food related. Any thoughts?