We have been debating this in our house for quite some time. My dd is 5 1/2 months old, and we have used the Miracle Blanket since she was a newborn, which has worked great! But, she is really close to rolling over back to front, and can wiggle her arms out of any swaddle (she's very persistent) and so I am nervous about continuing to swaddle her because of loose fabric being a suffocation hazard (when she wiggles her arms loose) and the risk of her rolling onto her tummy swaddled. But, there are times when the only way she can settle is with the swaddle. What we have started doing to wean her is that I only have her swaddled for 1/2 the night. If she is calm at bedtime and having an easy time, then I put her to bed in her sleep sack (sometimes still takes a couple of tries to get her to sleep). Then, at her middle-of -the night feeding I swaddle her, because she often gets restless in the late night/early morning hours. On the other hand, if she is struggling at bedtime, I swaddle her, and then switch to the sleep sack at the middle of the night feeding. I have no idea if this is a good plan, or just something my sleep-deprived mind cooked up :), but it does seem like she is getting more and more used to sleeping in her sleep sack. Try to find one that is somewhat heavy material, so that he can feel the weight of it on him, which might make him feel more secure. Good luck!