@Jami Thanks for reaching out!
We will give you some recommendations here in the community, however, we encourage you to think about scheduling a free virtual outfitting appointment with one of our product experts. They can talk you through the features and benefits of a backpack as well as any concerns you may have about fit. We also suggest checking out this Expert Advice article on How to Size and Fit a Backpack to learn how to make sure you're getting the best fit possible in your new backpack.
If you're carrying backpacking gear for your whole family, we recommend going with a backpack that is at least 65 liters in volume, and potentially more, depending on how bulky your sleeping bags are. Here are some options to check out:
As a sidenote, the Gregory Deva also comes in a 70 and 60 liter version, and the Osprey Ariel AG comes in a 65 and a 55 liter version.
For your 9 year old, take a look at these packs, designed specifically for growing backpackers:
When deciding what pack volume to get for your 9 year old, it is good to remember that a fully loaded backpack should weigh between 10-20 percent of your child's body weight.
Hopefully this helps gets you started, please don't hesitate to ask if you have other questions!