An acquaintance of mine who is a physician told this story about her then 4yr old daughter.
On the way to preschool, the doctor had left her stethoscope on the car seat, and her little girl picked it up and began playing with it.
'Be still, my heart,' thought my friend, 'my daughter wants to follow in my footsteps!' Then the child spoke to the instrument: "Welcome to McDonald's. May I take your order?"