Babysitting or sit on baby?

A young friend at church who loves babies (she herself is still a babe, being around 18 months) was completely enthralled with Annaliese. She didn't even want to tear herself away to do her favorite activity--craft. I jokily asked this little girl if she would like to babysit someday. She said yes and tried to sit on the baby. She looked quite perplexed when her mother plunked her in her lap and we mothers shared a hearty laugh.