Sharks give birth in one of three ways: they lay eggs and deposit them in a safe place for hatching (oviparity), they give birth to live sharks (viviparity) or they carry their young in egg sacs that hatch in the womb and then later give birth to live sharks (a combination of the first two methods known as ovoviviparity).
Many details of shark reproduction depend on the species of shark -- gestation can last anywhere from five months to two years, and a litter could number between two and 100 pups.
Talk about a sibling rivalry: Some species of sharks practice intrauterine cannibalism, which means they might eat fertilized or unfertilized eggs in the womb.
Sharks are independent once they're born. Hence, they may only encounter their mother or father in a random, dangerous situation, when the big shark tries to eat the smaller one.