Is it normal for 8 month old to twirl one wrist. it's not all the time and she is hitting all her milestones.

Probably ok: If she is making all of her other social, motor, fine motor and speech milestones then this is probably fine. She should be able to transfer an object from hand to hand. What are you most worried about? Any family history of developmental delay? A friend with a baby with cerebral palsy? Concerning Birth history? Be sure and discuss with your pediatrician at the 9 month visit.