OP here- last night I put him in footie pjs and a halo sleep sack (arms out) inside out. That kept him and he slept! I can't to the zipadeezip backwards because he'll turn it around.

My son also wore a sleepsack FOREVER. It helped ensure he did not crawl out of his crib. Put the Zippy or the sleepsack on backwards, they cannot reach it. Make sure to buy the sleepsacks where the zipper ends at the top - if it ends at the foot, kids can lift their feet up and unzip, even if it is in the back. Ask me how I know

Mine wore a La Petit Chose sleep sack from 6 months to 3

We just did footie pajamas.

I have this adorable image of my 1+ year old son standing in the crib with his sleeper and diaper at his feet looking at me and said "COLD"

I just started using a sleep sack after the zipadee zip. The Burt’s Bees ones have a little pocket where you can tuck the zipper to discourage unzipping. He may still be able to get out, though. My son went through a phase where he unzipped it every night for like a week and then stopped. We are still using them! I’ve heard some people suggest putting the sleep sack on backwards too (I tried this, but my son was not a fan).

My 18 month old can get his zipadeezip off, much to his delight. He is an AMAZING sleeper, in contrast to my other toddler who took years to sleep through the night. I'm worried he won't sleep without it. Is there something else I can try? He's a bit of a Houdini in general.