My son does not want to sit in his chair anymore

There could be a number of problems. Ask his nanny, if he struggles with her about the seat? Or if he ever did struggle with her about it? Maybe he knows you'll give in, and so is fighting you until you do. Maybe he almost slipped or fell when he was getting in and out of it and is scared of it? Maybe he just doesn't like the one you got? If the problem persists,and he still won't sit in it when you "lay down the law", I would suggest taking him with you and buying a booster seat, that goes on a normal chair. Let him help pick it out, and he may be more apt to sit in it. Explain to him that he is going to be able to sit in a big boy chair, and make it sound like a reward. Then put him in it when you get home, and if he throws a fit, he throws a fit... But if you think it's fear related, you'll have to use your judgement, you want him to know he can trust you when he's scared, but it is difficult to figure out when it is a fear, and when it is just a toddler being stubborn. GOod luck!

Hes probably ready to give it up. Seeing he wont use a highchair, and dosent like the booster idea. Here is what we did. We bought my son this little patio set, had 2 chairs and a table. Well we brought a table and chair inside and he has his own little place to eat. He thinks its so neat, and it solves our problem. He sits in a chair and eats at a table.

My son will turn two next month and so far have no problems about sitting in his high chair. Recently, he even got into his highchair himself with the help of a stool.

My daughter is 2 1/2 and about when she was just around two we bought her a booster. One that has no buckles or straps. It like a hard cushion and is slip resistant. It's very light and you can take it anywhere with you. My daughter loves to sit in it. You can find it at Onestepahead.com. Hope this helps. Tell him it's the Captain's chair or something fun like that.