She said she received a call around 9 p.m. Sunday from a medic at the festival who said her son may have been transported to the hospital, but they could not verify his identity. The teen had been traveling with friends by train to the festival each day from Mundelein, and one of his companions gave her phone number to the medic, his mother said. His Lollapalooza wristband, which serves as a ticket of sorts for the music fest, was of no help. The teen had purchased it from someone else and that person’s name was associated with it, his mother said.