Some snakes, such as boas, rattlesnakes and garter snakes, give birth to live young. That means that the baby snakes develop inside their mother. When they are born they are covered with a thin membrane, kind of like a goopy baggie.The baby uses an egg tooth to rip out of the membrane and wriggle free.ome snakes, such as boas, rattlesnakes and garter snakes, give birth to live young. That means that the baby snakes develop inside their mother. When they are born they are covered with a thin membrane, kind of like a goopy baggie. The baby uses an egg tooth to rip out of the membrane and wriggle free.