L.C.
Hi C.. Ask your pediatrician about Miralax. It's an OTC laxative that works very well. I have three kids that had constipation problems for different reasons and the doc told me to use Miralax. We tried mineral oil first but it didn't work at all for any of them. The Miralax has no flavor and can be mixed in with a bottle. I don't know if you have tried pear juice yet but that was one our pediatrician recommended even over prune juice. It always helped some.
Prolonged constipation can be the sign of other things going on. If it continues, I would ask the pediatrician for a referal to a GI specialist (gastrointerologist) and to have food allergy testing done.