service, and a probationary phase seems reasonable. If he messes up again, he should expect much harsher treatment from the courts.
On the civil side, it will depend on her injuries and future medical complications if any. Her medical expenses should be covered 100% as well as a nice payout for time spent rehabbing, loss of work, pain/suffering, and reimbursement for other expenses like lawyers/excess child care etc.
I think the Yewts will settle with her out of court. And I think the Gardners will settle this out of court too.
The civil issues alone do enough to deter everyone from thinking this is something you can do without consequences. The consequences for this kid are stark (even without going to jail) and are enough to deter the behavior going forward.