What will I do when his new baby brother arrives any day now??!

He was sleeping perfectly in his own room, until the seasonal weather arrived with lots of rain and thunderstorms during the nights so he would wake up scared and we'd bring him to our bed.

Then at the same time, a little over a week ago, my MIL arrived for her two month stay, idk why she is staying so long lol. But she sleeps in his bedroom now but bc shes a stranger to him, he would not stay in his room or his crib so we brought over his crib to our bedroom where he still wont stay in it.

So now he is reaccustomed to sleeping in our bed (after working so hard to sleep train him in his room and stay in his crib😭). And I dont mind having him here I'm just worried his sleep schedule will get messed by his newborn brother.

Has anyone gone through this?!