MOUNT VERNON, NY - NOVEMBER 18:  Singer/recording artist Usher attends the funeral service for Heavy D at Grace Baptist Churc
Mike Coppola

Usher's 11-year-old stepson Kile Glover—the child of his ex-wife Tameka Foster—was struck by a watercraft Friday afternoon and remains in critical condition, according to local reports.

The boy and a 15-year-old girl were being pulled by a boat on an inner tube on Georgia's Lake Lanier when the two were hit by a 38-year-old man riding a jet ski. The Georgia Department of Natural Resources already established that alcohol was not involved in the incident.

Glover and his companion were airlifted to a children's hospital about 40 miles away from the lake. Glover's injuries are reportedly more serious than the girl's, and officials said he was unresponsive at the scene. Georgia's DNR is investigating the collision and will help decide whether charges are to be filed.

2012 has been a tough year for Usher. The R&B star began a contentious child custody battle with his ex-wife in May (they have two children together) and he weathered a stalker scare in June.

Both Fantasia Barrino and Russell Simmons have taken to Twitter to urge people to pray for the 11-year-old boy. "Everyone PLEASE pray for Usher and Tameka's son! This is the time they really need your prayers!" wrote Barrino.