MTElkChaser
WKR
If there’s an REI near you - take her there to get measured for a pack. I’ve found that they’re pretty good at measuring in my area, but ymmv. Then you can decide if she needs a hunting pack and feel comfortable that you at least have an idea of what size she’ll need. I did that with my kids and got both of them packs that actually fit their torsos and were comfortable under load. Good luck!