My female will be giving birth tonight, this will be our second litter. The first time I put a nice nest box full of hay in there. She took all the hay out and just made a nest purely of her own hair. It was a great nest, kept the bunnies warm and worked great. This time I put the nest box with the hay in there and she just sits there with a mouthful of hay like a dog with a bone. She tore all the hay out so I assume she'll fill it with hair shortly before birthing. Is this normal? Do your females use the hay/bedding or do they make a nest purely out of hair?