Lots of excellent points from the informed members of this forum!
I don't ride (though I would like to

), and I can tell that Triumph is a lotta bike for starting out!
Speaking as a concerned parent, I would be fearful for the insurance premiums AND your safety. I did go to a training course once and I was told over and over how no one teaches you to look out for anything but other cars in driver's Ed, so you always have to look out for other drivers doing things in front of you simply because you are practically invisible to them.
I doubt I (or actually my wife) would let my daughter get a street motorcycle when she's older...but for now, she's having a blast!
If you don't plan on doing more than 30 mph, here's a suggestion: