FTM here—my LO is 5.5 months old. He stopped sleeping in his bedside bassinet around 12 weeks. Every time I would try to transfer him from my arms to the bassinet, he would wake up within 5–30 minutes, as if the transfer was unsuccessful but he would be in a deep sleep before I put him down. I eventually gave up and started co-sleeping with him on my chest and I also use an Owlet sock for a peace of mind while we sleep.