The word babysitter first appeared in year 1937, while the verb form baby-sit was first recorded in the year 1947. The American Heritage College Dictionary notes that one normally would expect the agent noun babysitter with its -er suffix to come from the verb baby-sit, as diver comes from dive, but in fact babysitter is first recorded in 1937, ten years earlier than the first appearance of baby-sit. Thus the verb was derived from the agent noun rather than the other way around, and represents a good example of back-formation. The use of the word "sit" to abbreviate to refer to a baby-sitter is recorded from 1800. The term may have originated from the action of the caretaker sitting on the baby in one room, while the parents were entertaining or busy in another.
Chickens May Be the Real Mothers of the Word – The settling upon the term “sit” to mean “caring for” is shrouded in mystery. Many etymologists theorize that the word stems from laying animals, such as hens, who sit on their eggs to ensure their warmth and safety.
Do you know, some babies have memories of their past reincarnations or past lives. You can discover this easily by observing their thoughts or talking to them directly about it. So be wary or amused that they may be someone you knew or even someone wiser than you.