Babies

Okay so my boyfriend mother give birth a month Ago to a baby boy. And she's gives him breast milk but seem like when he drinks her milk he will get gassy and miserable after drinking it. He will cry for a hour because it's makes him so uncomfortable. She's starting to put formula with her breast milk and gripe water and he still throwing up. I'm lactose in tolerant when I drink milk I will get gassy, and I feel throw Up. And what I learned is my boyfriend mother boyfriend is lactose intolerant too. I have told her to put the baby on baby formula is that a good idea ? It must have a lactose intolerant formula for babies right ? I know breast milk is great for babies but it seem like it not agreeing with the poor Guy 👶💔