Babysitting already???

I'm having a "old" moment.  My friend/neighbor called me and asked if Mac could babysit.  Her baby had just fallen asleep, which he hadn't done all day long, and they were planning on going out to eat.  They didn't want to wake him up, so that's where McKenzie came into the picture.  So really it was going to be "please sit in my house for an hour and call your mom if the baby wakes up," type of babysitting.  She has a long range monitor so we plugged it in so she could call out to us if she needed me or Randy.  I know she is only 10, but she is sooo excited to start babysitting.  I'm really excited for her to start babysitting too ;).  I started babysitting at 8 (granted I'm number 4 of 9 and was changing diapers before I was pottytrained), but it feels weird to have a kid almost old enough to really babysit.  Double digits was hard enough.  What's going to happen when she goes into Young Womens?  From my perspective, however, I feel like she is really mature and knows how to watch kids and keep them out of trouble, she usually does that with her siblings.  What is the legal age for babysitting anyway these days?  Anyway, I just had to share my "old" moment. . . can I stop the clock pleeeeeeaaaaassssseeeee???