Creepy little girl...

So I'm a part-time nanny for our friends who have a 3yo girl and 15mo boy, and today the little girl, Zoey, said something really creepy to me!
Out of the blue during lunch, in the middle of a happy little chat about her friends at preschool, she turns to me with a suddenly really serious face and says, "Make sure you don't fall and drop your baby." I said, "What? I'm fine, Zo, I'm not gonna fall!" She shook her head and said, "You're gonna fall and get hurt, and your baby is gonna come out and die. That's sad." I stared at her in shocked silence for a few seconds, and she suddenly smiled again and started singing "Let It Go" like nothing happened!
It scared the crap out of me and I'm sure it doesn't mean anything but man, I'm being extra careful! šŸ˜‚