That sound FUN!
I have just about settled back on the 223. Partly because she can shoot her G-site laser all day in the house. But also because when I said she was a little little girl, I was serious. She is 41" tall and weight 36 pounds.
I love the idea of a 6.5 or a 7-08, but its just too soon for her. I'm mostly interested in helping her develop good habits and keeping her interested. There are two more coming up behind her so it will get plenty of use as a hand-me-down. I'm still mulling over the less than satisfying stock choices for a bolt gun in super compact sizes. There is a big hole in that market.