Yes poor diet can effect your immune system. Also them feeding him all this crappy food, is going to make him obese! And being an overweight child isn't anyfun! Besides the health problems from being an obese child, he will also get picked on @ school and probably have emotional problems... They need to start feeding him right! More veggies & fruit, less fried crap, & since he's 14 mo he really doesnt need baby food, but he should eat gerber graduates. They have all the right stuff in it for a healthy diet! Tell them that he needs to eat more healthy... I have a question though, r they fat (not tryin to be mean)...that just has a lot to do with what ppl eat & feed their children.