I've got a 12lb goose that I've seen run face first into my electric fence wires... if the Goose is ok, I'm sure your daughter will be.
There's no current to these things anymore - they really can't do much damage.
Modern electrical fence chargers are very different than old-school ones.
The older ones had a couple of problems:
1. Some were always-on - basically you'd touch them, your muscles would contract, and you couldn't move much - this was the typical reason for animals getting stuck in them and...