In light of the concern expressed about her outgrowing one of the mini-sized bolt guns too quickly, another option occured to me. I think it's something worth looking into, as it offers some real advantages in several respects.
I started all of my nephews and nieces out with a Chipmunk ss BA when they were quite young. It worked beautifully and was one of the very few "kid-sized" .22's made back then.
When my youngest nephew was getting discouraged because his smaller stature made it extremely difficult for him to make the transition to full-sized repeaters with his older brother, I feared that he would lose the enthusiasm he'd always shown when a range foray was mentioned and drift out of the sport.
The LOP on all of my other rifles made taking a solid position, sighting and even some action manipulations too awkward for him to be able to stay "competitive" with his brother in his skills, and that became a real issue motivationally. Anyone who's ever had a sibling will understand.
Being stuck by default with the little ss and watching his brother demolish the majority of the cans and clay targets with a repeater made him feel like he was at such a disadvantage that he couldn't 'win' no matter how hard he tried. Not good.
I found out about Rossi/Taurus' optional 'Youth'-sized butt stock for the excellent little M-62 gallery pump. As I have two, and one of them was playing a prominent role in our little drama, I ordered one and installed it before their next visit.
With both of them identically equipped he was soon pushing his older sibling to match his scores, which turned out to be good for both of them.
I really think that the gallery-style pump action with an exposed hammer makes a truly great first rifle for kids.
It's easily single-loaded, offers positive visual verification of firing status, has a relatively simple manual of arms for both firing and administrative handling and is just as rugged and dependable now as they were when they were the mainstay at arcades and midways all over the country.
Even though the boys have many other options now when we go out to the range, some with scopes or Red Dots and more high-tech looks and features, the old Rossi pumps remain the most requested items to take along.
Heck, their old uncle hasn't even outgrown them yet and he shot his first one over 50 years ago.