What are the “rules” for leaving baby to sleep alone if you’re room sharing? On my 3rd baby but I’ve always wondered. I room share… 1 year with my first and 6 months with my second. 3rd is now a newborn and is room sharing but he sleeps alone sometimes, is that bad? For example, generally he naps in a pack n play in his own room because I’m busy with my older two or getting things done around the house. At night he sleeps in his crib in my room, but my routine is that once I put him to bed, my husband and I spend a few hours together downstairs before going to sleep in our room. So for the first few hours at night, baby is by himself. Is he still getting SIDs protection if he’s alone at times while sleeping? Surely no one is spending every daytime sleep trapped in their bedroom right?