One of my daughters moves a lot when she sleeps; from small, the sun rises with the crib (now bed) undone and the blanket at the feet. Concerned that my girl could suffer too hot or too cold, I commented with my mother-in-law, with other mother-friends, with neighbors and I asked all of them the same thing: “What can I do to keep it from uncovering??”.
I heard all kinds of answers, but the one that horrified me the most was the use of tweezers to hold the blanket and the sheets to the bed. I think that using tweezers or other devices to fasten the padding to the crib is inconvenient and can also be very dangerous. The baby is able to free himself from the quilt or blanket in case they accidentally cover his face, but if they are tightly tied to the crib, and the child slips down during sleep, he may not get uncover without help, with the consequent risk of suffocation.
If what you fear is that your baby gets cold during sleep, I recommend that you try to dress him with an entire pajamas (“teddy” we tell this garment in my country) or you will buy a sleeping bag that is wide. This way you will have your belly and feet covered and, in addition, you can move without obstacles and will not uncover. Also try not to shelter the baby in excess, because heat can be the reason why it is constantly uncovered. Keeping the baby's room at a temperature that is comfortable for you is ideal in these cases.
When you grow up, you will see that it self-regulates: it will be uncovered if it feels hot and it will cover again if it is cold at night.
