My nephew always slept in his swing and to be honest with you his back looked weird, like a football players. My sister in law and brother would wrap him up like burrito and prop a bottle and put him in his swing. One day I cried when I saw him, I saw it as neglect and cruel. He can't get out, he can't roll over, he can't stretch! And he always carried his arms weird. He would get mad and scream when you'd lay him on his back. He's 16 months now and his body still looks odd. He has a 2 year old brother who didn't sleep in a swing and his body is normal proportion wise. I wouldnt recommend it. Maybe for naps but not over night. They cant roll over, stretch out, move much. Imagine how sore and stiff you'd be if you had to lay in the same position for 6 hours. Why risk it?