My DD is 4.5 months old and sleeps in a Miracle Blanket swaddle. She's starting to roll onto her side in the day and getting too long for the swaddle, so I want to transition her to a sleeping bag. The problem is, she gets really distracted and eventually distressed by having her arms free at night. She can be all lovely and drowsy when I put her down, then her arms start waving around and she wakes right up. It's like she doesn't know what to do with them. It's not startle reflex, I think she just finds it really distracting / stimulating. I've just been trying to get her to sleep for an hour with one arm out of the swaddle and have had to give up. As soon as I put the arm back in she was out like a light.
She can take daytime naps in a sleeping bag, but that's in a rocker chair so she has motion to help her.
Any advice?