If your baby is ebf it’s unlikely she will even take a bottle of formula. For one, it’s a bottle and most ebf babies prefer nursing, especially to fall asleep. And two, formula tastes way different than breast milk and she might not even like it. Also it’ll probably upset her stomach which will keep her up during the night.

You can’t force a baby to sleep longer. They all do it eventually, and when they’re a little older you can sleep train them and help them to self soothe. There’s a huge sleep regression at 4 months but not all babies go thru it. My daughter did and she woke up every hour and it was rough. My son on the other hand didn’t experience it at all and has been sleeping 9-10 hours at night since he turned 3 months. You just never know.

I started giving my baby formula with a bit of cereal at 4 months and that’s when she started sleeping more before her belly was fuller. But when I which from breath milk to formula nothing happened. She just wanted milk faster because she knew I could make more faster plus I think she liked the taste better lol

It’s not true. Sleeping through the night is a developmental milestone that babies will hit when they are ready. It’s not dependent on what they’re eating. Formula is harder to digest and could be hard on your daughter’s stomach, which could cause her to be up more because she’s so uncomfortable. Plus, not feeding at night could impact your supply.

No definitely not!! I dont ff but I know that babies wont sleep differently with different milk or food. If shes never had formula it could also upset her tummy before bed and keep her up. Sleep is a learned skill. Shes still way too young to sleep better. I'd suggest just trying to keep a routine as much as possible, have someone else do bedtime/nights if you can