Every time my 18 month old has to poop he gets a pained look on his face and fusses through it. He tends to have pretty big and very hard solid poops. This has been going on since I day weaned him. He usually poops every two days but sometimes daily. I'm wondering what if anything might help him. He eats a lot of yogurt, noodles, quinoa, bread and apples. I was thinking of adding some prunes to his lunch. Any suggestions???