Please do not put a sheet over a sleep bag....
Why ever not @DontWantToAdult?
You can get:
● Many different you ratings of sleeping bag
• 0.5 tog
• 1.0 tog
• 2.5 tog
• 3.5 tog
● Many different sleepwear clothing to wear at night:
• just a nappy
• nappy + short sleeved vest
• nappy + long sleeved vest
• nappy + short sleeved vest + sleepsuit
• nappy + long sleeved vest + sleepsuit
• nappy + short sleeved vest + fleece sleepsuit
• nappy + long sleeved vest + fleece sleepsuit
All if these are so that parents can adjust their baby's layers according to the room temperature.
Absolutely no reason why you can't:
■ Go down a you rating on your sleeping bag and add a cotton sheet over the top
■ Put baby in less clothing (just a vest instead of vest plus sleepsuit, for example) and add a cotton sheet over the top of the sleeping bag.
I tightly tucked in sheet is a long establishesd (and totally safe) way to help a baby used to swaddled to wean off them.
As an aside, there's a class issue at play here. What you might not realise in your hysteria at using a sheet over the top of a sleeping bag is that there are families out there who cannot justify the cost of buying different tog rated sleeping bags for their babies, nor indeed fleece sleepsuits (which are often the same price for 1 as you can buy a pack of 7 plain white cotton sleepsuits).
Such families may well make-do by buying only a summer weight sleeping bag and over the winter months adding sheets and blankets over the top of baby in sleeping bag (Feet to Foot).
This shouldn't be a revelation.
This is totally safe.