Residents are invited to a March 21 screening of “If Only,” a short film intended to raise awareness about the dangers of young people misusing and abusing prescription medications. Created by the Mark Wahlberg Youth Foundation and Millennium Health, the 38-minute movie was filmed in Tewksbury with local actors. Mark’s brother, Jim Wahlberg, produced the film and will provide an introduction. After the screening, a panel will answer questions about prevention, treatment, and recovery. The event will be held from 5:30 to 7:30 p.m. at the Malden YMCA, 99 Dartmouth St.John Laidler can be reached at firstname.lastname@example.org.