Are you positive?
Possibly using Johnny Knoxville, Bam Margera and Spike Jonze, dressed up as their finest elderly counterparts. The 3 should go to a local Free Health Clinic to be tested for STD's. They should argue in the office and make it clear there is a love triangle in the nursing home where they live. Also that Jonze's character is a real slut. One could bring a teenager with them posing as a grandchild, to "teach them a valuable lesson about whores" at an early age. As loud and graphic as possible. The clinic wont know how to handle elderly people with this type of dilemma. Ask for free condoms on the way out, however many they give, ask for a couple more to be safe.