Husband wants to give 3 Month old cow milk

Hello ladies, I need some advice or just ranting here. I have a 3 month old turning 4 on the 30th. Me and him are going to Mexico for 2 weeks. i told my husband that i didnt want to give my baby any solids till he was past the 6 month mark. He said he understood and tha he would tell his parents. Well yesterday he tells me that the only thing he'll want the baby to have in Mexico is cows milk. Literally straight from the cows tit. I told him that was not happening so he get mad.

Then the other day I asked him how he wanted our son to call his mom when he was older. "Abuela(grandma), or Welita(granny)" hes like I want him to call her Mom. I said no not happening. So today he said to my son " you want me to call Big mom (his great grandmother) or Little mom(his grandma)" I told him to stop saying that. He blew up saying that I can tell my son to call my dad whatever he wants but not to be telling him about his mom or grandma. SIDE NOTE: MY HUSBAND DOES NOT CALL HIA GRANDMA MOM. HE CALLS HER GRANNY(WELITA) and he says she's his world. so I dont get it

Now I know yall may think I am exaggerating but I dont want my son to call them that because I am his mom and those are his grandma's. I am not going to tell him to call my dad daddy or my birth mother mom or mommy so why should he.

I honestly dont know what to do.

I dont have a mom of my own. She left me when i was 2 years old. I honestly do not want my son calling anyone mom besides me. It just doesn't feel right to me. My husband does because it's like he wants my son all to himself. He'll tell my son ewww there's your mom the witch and laughs. And even though he's only 3 months he's trying to get him confused. I'm taking him to Mexico to meet his parent's, I do everything to please him. And the only thing I ask is for him not to tell my son to call his grandmother that.