@GMF yeah I makes sense I use the blankets that are recommended for babies so he is safe with it the blanket is the same ones as the hospital ones
The lullaby trust has info on safe sleep - you can use blankets as long as the guidance is followed. Our little one is also dinky, love to dream do a swaddle for over 2.3kg I think it is, but is too tight round the tum for her now. We're waiting for her to get into range of the smallest tommee tippee ones . We found pulling the scratch mittens over, which helped keep her hands warm and stay asleep a bit longer
https://www.lullabytrust.org.uk/wp-content/uploads/The-Lullaby-Trust-Product-Guide-Web.pdf
Try stuffing the blanket down your top or having it between you and baby so that when you put him down the blanket is warm and already touching him, then when they've settled a little more into sleep you can readjust. Or wrap/swaddle their lower half with the blanket before you soothe so that when you put down they don't get disturbed. Other alternative is thicker sleep wear so you don't need to worry about a blanket or anything else, or increasing the temp of the sleep space a bit with a space heater again so you don't need blankets. X
Blankets are not safe for sleep until age 1, baby doesn’t need to be swaddled or in a sleep sack either, pajamas are fine just adjust temperature accordingly! You can also swaddle with a blanket like the ones used at the hospital, baby definitely shouldn’t be too small for that. So you could swaddle with the blanket first, then place baby down asleep. But not just place a loose blanket on them in their sleep space. Hopefully that makes sense!