Hi, my baby is just over five months and can roll from her back to her tummy. We put her to bed on her back and often find her sleeping on her side and just leave her. Lately, however, she has started to roll onto her tummy for sleep but she cannot roll from her tummy to back. Should we just leave her or keep rolling her to her back or side until she can roll from tummy to back? She also sleeps in a bassinet with mesh sides that allow air flow. Should we be transferring to a cot soon if she can roll? Thank you.

What you are describing is normal development.
Most babies will be rolling over by 5 months…....some earlier, some later.
This is very normal as babies grow & become stronger many babies then prefer to sleep on their tummy, & often don’t change from that position.

This is not something that needs to be stopped, but it is important to make the environment as safe as possible for this to occur.

Always place baby on their back to sleep.
Ensure cot mattress is firm, well-fitting & flat.
Ensure there is nothing loose or soft in the cot.
Move from bassinet to cot
Use a sleeping bag now that has appropriate size neck & arm holes. - cease wrapping, she needs her arms out

It is essential to discontinue wrapping as soon as baby starts showing signs that they can begin to roll, usually between 4-6 months.
If you are using a bassinette it is time to transfer your baby into a cot as soon as they first show signs of being able to roll

Red Nose has the following information now that your baby is starting to roll.

Give baby extra tummy time to play when awake and supervised as this helps baby to develop stronger neck and upper body muscles which in turn enables them to roll back over.
Make sure that baby is on a firm and well-fitting mattress that is flat (not tilted or elevated).
Make sure that baby’s face and head remains uncovered (do not use lambswool, doonas, pillows, cot bumpers or soft toys)

As babies grow and develop they become very active and learn to roll around the cot.
At this time, continue to put them on the back at the start of sleep time, but let them find their own position of comfort.
By this stage it is not necessary to wake during the night to turn baby over to the back position

Do not use any devices designed to keep baby in a particular sleep position.
https://rednose.com.au/article/what-do-we-do-now-that-a-baby-has-started-to-roll-over
https://rednose.org.au/article/is-it-safe-to-use-products-designed-to-keep-baby-in-a-particular-position