We had a baby this past April, and we have 4 buns in the house ranging from a year to 4 years at the time she came home.
What we did was prepare them the same way you prepare a cat or dog… find some clips of babies crying on youtube and play them on a low sound setting until the bunnies are comfortable with it (as if it’s muffled from another room) on and off each day. Gradually increase the sound but each time you increase, wait untll they are comfortable. Give them extra treats for approaching the source of the sound to investigate. By the time our little one came home none of the buns were phased by her crying… but they still had their limits before they hopped off to the other side of the room.
Make sure he has a safe place where he can feel hidden, and that his food and water is near by in case he decides to hide for a while. He’ll adjust, but he’ll be okay. Our bunnies love our little girl, though they seem to understand that she’s not got much motor control for petting yet… my bigger pair put up with some rough petting, the smaller pair come up and kiss/nudge her as long as they think her hands are occupied. ^_^
TIP: make sure to keep baby bottles, pacifiers, and teethers off the floor as bunnies LOVE them! lol