My son just turned 3 months old last week, and has outgrown his bassinet. I've read online that it is safe for infants to sleep in a pack and play, as long as we are room sharing (which we are).
But I've noticed that ever since moving him from the bassinet to the pack and play, he's been sleeping much more deeply than usual. Normally at night, he would rotate his body in his bassinet, and wind up with his head and feet up against the short ends of the bassinet - which is why we moved him to the bigger pack and play. He would also wake up in the middle of the night for a feeding and changing, and then again in the early morning for another.
Now though, he's had one night where, other than shifting around a bit, he hasn't woken up at all. He will occasionally shift his body, sometimes quite forcefully, but falls right back to sleep afterwards. And last night, he only woke up once for a feeding, again only waking up otherwise to move his body - usually by lifting his legs into the air and then kicking them down into the pack and play mattress.
In addition, when I lifted him out of the pack and play this morning to being our daily routine, he was deep asleep, still moving but so soundly asleep that he didn't even wake up during his diaper change, and only truly woke a few minutes after as I was getting him positioned for a feeding.
I know this might seem strange to worry about - many new parents I'm sure would just be happy to know their child is starting to sleep through the night. But, is the sudden shift of significantly deeper sleep a cause for concern? Or is my infant son simply experiencing the normal transition into longer night sleeping?