If she was WALKING her bike in the crosswalk, then she should have any medical bills/property damage covered by the driver--just as though she were a pedestrian.
If she was riding it in the crosswalk though, she's going to have a harder time arguing her case. A friend in college got hit by a car on his razor scooter while in a crosswalk, and
he was deemed at fault, because, as the police said, "Crosswalks are for walking, not scootering"
Regardless, I'd call the police and file a report, just so it's on record.