If the scull is fused the individual is not a baby
Explanation:
If a skull is found, one of the first things to do is classify by age. Careful observation will show that the skull may or may not be fused. Noteworthy observations could give the professional an idea of the individual's age.
In the womb when the bones of the skull are being formed thre are typically seven bones with gaps in between. This allows the infant to pass safely through the birth canal but giving way to squeezing and the contractions of the uterus. After the child is born there are still remaining gaps. These gaps allow the brain to grow and develop without pressure from the skull. This can often be observed by a soft spot on the top of the infant's head sometimes called a "mole"
Around two years of age, these bones begin to fuse and harden. Therefore if a skull is found with fused bones, the individual can be placed to be older than two years of age. Other determining factors such as teeth etc can narrow down the individual's age.
