All baby organisms all called offspring. Baby cottontail rabbits are called kits
An adult is 2x the size of a baby.
Cottontail rabbit babies, also known as kits, are born blind and hairless. They have a distinctive white spot on their forehead and are very small in size. As they grow, their fur becomes thicker and they develop their signature cottontail.
2/3 of the size of an adult brain
They are about the size of adult mice, but some are smaller.
Roughly the size of a human adult pinky finger.
baby's weigh 20 to100 pounds
When a baby lion is born it is about the size of a small adult cat
Not that i know of. we had several baby rabbits after saving the mother cottontail from our dog and when they roamed around with other older rabbits, they didnt harm the babies at all.
A baby cottontail bunny will typically nurse until the age of 4 or 5 weeks at which time the mother cottontail will wean the baby. After the baby cottontail bunny has been weaned it can easily feed itself on grass and other vegetation that it finds.
Size
this is not a reliable website because a baby could answer this.