I am a law school graduate. What I offer is mere information, not to be construed as forming an attorney client relationship.
Here is my take and I have been through something similar:
1. Your daughter is liable as driver.
2. Your daughter's friend is liable for negligently entrusting her vehicle to your daughter.
3. If this friend's parents own the car, they may be liable if they knew your daughter drove.
4. Same theory with you -- if you knew your daughter drove.
Factors to take into consideration:
1. Your daughter's age
2. Her driving record -- any accidents or tickets other than this?
I don't think under this scenario you and your spouse would be liabel. Also, even if your daughter was and the judgment exceeded any and all insurance amounts, good luck in collecting from a 16 year old, even if judgments can be attached for up to 10 years.