Sleep in their own room

We have a 3 year old daughter, soon to be 4 in May who used to sleep in her own room since she was 2.

She could sleep without waking up in the middle of the night but now, she sleeps in our bed.

Now we have a 3 month old baby that has to sleep beside me or he won't sleep at all. Our daughter keeps moving around and accidentally kicks or hit me or the baby when sleeping which upsets me.

So we're trying to make our daughter to sleep in her own bed again but she refuses and will wake up immediately after we put her to sleep.

Her dad is too nice and wants her to sleep with us but I'm tired of getting kicked or slapped by her when she's sleeping between us.

Does anybody has any advice? 😣