Monster Update: 17

The Tummy monster weighs about 5 ounces now, and it is around 5 inches long — about the size of a large onion (pictured). The umbilical cord, the lifeline to the placenta, is growing stronger and thicker. The Monster can move its joints, and its skeleton — until now, rubbery cartilage — is starting to harden into bone. Some of it will remain cartilage for years after birth. A newborn's skeleton has 300 parts (a combination of bone and cartilage). As children grow, some of these parts harden and fuse together. By the time the Monster reaches adulthood, it'll have just 206 bones.

Text adapted from Baby Center.