My 3 year old will not eat anything but scrambled eggs, hot cereal and sweets!  He is very thin; however, my 10 month old SWCAH son will eat ANYTHING!  I often wonder if it has anything to do with the way I fed him as an infant.  I was very particular about what he ate.  Our 2nd eats whatever we eat and is a much better eater.  He does lose his appetite a bit when he  is sick with ear infection, but all in all, I think it is just a toddler thing.  Good luck.