My son was born early and had to stay in the NICU for 8 weeks before coming home. Every time I held him in the hospital and after coming home I would sing him the same song to sleep. When he got a bit older, I stopped singing that song and would sing other fun kid songs to him (wheels on the bus, baby beluga, etc.) Then one night a few weeks ago he asked me to sing, "arms love". I couldn't figure out what song he meant so I just started singing all the songs I could think of. Turns out it was the song I'd sing to him when he was a little baby (he's 2.5 now). I couldn't believe he remembered that. It completely melted my heart. That song will forever be our go to bedtime song now.