my 3mth old girl keep sleeping on her right side since birth and now right side of head is a bit 'flat' and some advice me to let her sleep on yaolan... will she be relied on yaolan? should I let her sleep on yaolan? troubled....

I have read that it could be due to her neck muscles being stronger on one side, so a common suggestion is to try and have more tummy time to help strengthen her neck muscles. Due tummy time, use rattles and toys and try to get her to turn to her left. Another suggestion is to twist a towel into a horseshoe shape and place it around the baby's neck when she lies down. With regard to the use of yaolan, I think you will need to consider carefully. There is no guarantee that it will help even out your baby's head I think. Most parents consider this option more to help their babies sleep. I think you can try asking your doctor at her next checkup, whether the "flatness" it is a cause of concern. Sometimes, babies will move more as they grow and may reduce the flatness. Otherwise, doctors may recommend some physiotherapy exercises to help. Hope this helps!