Don’t know where you’re located, but there are parkour gyms popping up all over the place, and most have kids classes. They may go by ninja warrior gyms or be combined with climbing or gymnastics gyms. These gyms are often designed with kids and safety in mind, and will teach kids safe, sustainable movements

Another option is to scout a local parkour group. The one I’ve attended events of most in the past, SF Parkour (in the SF bay area) has events specifically for kids. You’ll want to vet the groups of course and likely be present as they’re not daycares, but you may be surprised how many parkourspeople are knowledgeable and mindful about safety and developing sustainable body mechanics. There are some reckless groups and members out there for sure, but most are rather cautious

Parkour is a meditative practice for most I’ve encountered and seen online, though that may be NorCal thing and online self-selection. Scouting some strong mentors and content from online communities that reinforce learning one’s limits and safely expanding them will likely encourage her to do the same. Can’t speak more highly of Raul Piscoya, the guy who runs SF parkour