I have a 9 week old fd who came to me at 3 days. I had her sleeping with me from the start, simply because I was afraid of dropping her in my exhaustion with the every two hr feedings

.
Now that she is sleeping around 5 hours at night, I keep her with me until her last feeding, then place her in a bassinet near the bed. Depending on how long she is with me, I want to get her into a crib once she sleeps through the night, simply for my own needs (SLEEP!!!!).
I also have a 2yo fs who has come into my bed a couple of times after waking up from a nightmare. This experience has taught me that I do NOT want a toddler in bed with me.....it's like sleeping with a hyperactive starfish - you constantly have a foot or hand in your face.
I rather agree that it depends on the kid and the parents and what works for them.....