T.T.
Stand up to his family and let them know that it is your child and not theirs! That what they do cause him harm and if they had any feeling for his health and well being they would not give him something that WILL make him ill. Their spitefullness is only hurting him.
If they dont listen...instead of rushing him home tend to him at the party and let them see how sick he gets right in front of them. So then your husband wont have any ground to stand on when he say's its all in YOUR head.
My husband has a hard time understanding that our daughter is lactose intollernt. He tried to give her regular milk at 12 months and she of course threw it all up on me. He also forgets to buy Whole Milk and buys low fat. I have to remind him that she needs Whole Milk for brain development. He thinks the lactose intol. is all in my head. I remind him that it is genetics and not my mind. I am lactose intol and so is my father and so is my grandfather. I told him since I am the one who feeds her and takes care of her all day long that I determine what she eats! End of discussion...next day he went and bought Lactate Whole Milk with Fortifide Calcium. I guess I won that battle.
I can understand the battle with the inlaw's. He had an issue over our daughter's weight...they thought she was fat and kept bringing it up to me. I would always have to give a list to them of what she eats. The last straw was when his Mom said "I know this is a sore subject for you but..." then it started regarding her weight. She is a baby was was at the time and she was Chubby as was I. There was nothing wrong with her Ped said so. So I had had enough and said if one more person brings up her weight that I was going to let them have it! It is my baby not theirs, they have their kids and raise or have raised them the way that want. This one is mine and I will raise her the way I feel is best. To be honest is better than what they do or did. I just dont want her growing up with a weight complex and end up with a eating disorder. Thank god they live over a hundred miles away!
Good luck to you and yours! Stand Strong!