They're blind, and weigh in at one or two ounces each. There are usually four in a liter. The mother will keep the young in the nest and nurse them until they're ready to venture out of the nest, on their own. This is usually in eight to ten weeks. You may see a mother squirrel move her babies, she will carry them by mouth, one at a time.
Squirrels are solitary animals.
They do not have a hierarchical structure, and therefore, no group name was established. They are called babies or infants while in the nest. Then for their first year they're referred to as Juveniles. After their first year, they become adults and are simply called squirrels. No, the male squirrel leaves after the mating.