A teacher at my H.S. was telling my cooperating teacher about seeing another teacher's new baby over the summer. The first description she gave was that the baby was "very well-behaved."
What does that mean? Most people would answer that the baby doesn't cry a lot and might sleep through the night. There are three personality types for babies and you can look that up. Experts say that a baby's personality doesn't necessarily coincide with their personality as they grow. The "personality" just decsribes how "needy" or "demanding" a baby is.
A baby does have behavior. A baby behaves in the necessary way to get what he or she needs: changing, feeding, sleep or to let someone know he or she is overstimulated and overwhelmed or uncomfortable in any way. Regardless of the baby's personality type, when a baby is described as "well-behaved" that really means the PARENT (or caregiver) is well-behaved (i.e. meeting the baby's needs).