Mmm that's a tough one. I've heard that around 2 weight gain slows so they don't need as much food and also developmentally they can't sit for long so graze throughout the day. Does he go to daycare? Maybe chat to them, they usually provide good meals in centres and if his friends are eating then he probably will too. Could you give him snacks like cucumber, tomato, capsicum through the day with hummus and mountain bread or crackers. Steamed veggie sticks etc? My daughter loves to dip and loves lots of little things to nibble. You could do fruit sticks and yoghurt to dip fruit into. All you can do is to continue to offer healthy options, if he's hungry he will eat. So long as he is getting enough during the day he will be ok. It's hard of there's pressure from others to have your child sit and eat a meal but it really could just be a developmental phase.