Hi ! Congratulations to both of you! The hair fall post delivery is called Telogen effluvium. It usually starts a month after delivery and lasts for around 4 to 6 months. During pregnancy all the hair go into a growing phase and do not age or do not shed. But after delivery those hair go into a resting phase and are shed. They will grow back with time. Let her continue iron calcium and folic acid supplements. She should eat properly and keep hair oiled as much as possible. Hair fall though seems scary should not be a concern since they would grow back. Hope this helps.