My daughter did not call the police?

Your daughter shouldn't need to worry too much because she was struck from behind, and unless she had stopped in the road for no reason at all, the person who struck her would likely be found liable. That's not 100% certain, because the person in the rear may claim either the other person stopped suddenly for no reason, had no working brake lights, or backed into them rather than them striking her. She has little to worry about, but people sometimes do strange things. Your daughter could have reported this incident to the insurance company just in case something should come up, but if your daughter wasn't concerned enough to call the police, then it should be fine. She should however document everything that happened...any photos of damage, time and location, and the other person's information, just to be safe.

The person in the rear is NOT always the guilty party. However, since neither party contacted the police at the time, then the fault would automatically go to the person in the rear. I doubt she would try to take any action now, as she would be deemed at fault.

without a police report, your daughter is at risk of the woman lying about the damage.

hopefully she took some pictures with her cell phone in case the woman decides to sue for more damage that what occurred.

She could come after her but is pretty evident that she would be the one on the losing end so its very unlikely.