My LO is 7 wks old and will only sleep on his tummy. The only other way we can get him to sleep is if he co-sleeps with us either in DP's arms or in mine.
If we put him on his own on his back he gets very upset and won't settle for more than a few minutes even if we swaddle him. When we put him on his tummy he settles instantly and when he wakes he's very relaxed and rarely cries.
What are your experiences of this?