Mark Jaster and his wife, Sabrina Mandell, got good reviews last winter starring in Round House Theatre’s The Seven Ages of Mime. But they are bigger stars at Children’s National Medical Center, where once a week they play Doctor Baldy and Doc Molly as part of the Big Apple Circus’s Clown Care Program.

The program brings clowns to Children’s, Johns Hopkins, and other hospitals. Using juggling, mime, magic, and music, the performers entertain sick children, family members, and staff.

The kids get to call the shots, deciding whether the clowns can enter the room. “Sometimes we just start juggling in the doorway until they decide it’s okay to come in,” he says. The two might blow bubbles or pretend to be an animal of each child’s choosing.

“The key is keeping a hand on the dial of the performance,” Jaster says. “We may pull out the shower nozzle and spray water at each other or simply play quiet chimes next to a kid during a painful procedure.”

Jaster, 52, has been Doctor Baldy for ten years. When not playing a clown, he and Mandell run a theatrical company called Happenstance Theater. Although he’s been a performer for more than 30 years, he began with the program at the time he lost his first wife to cancer. Two years ago Jaster, who has three children, met Mandell at—where else?—an eight-week clown workshop.

Jaster recalls a time when he was trying to get a listless teenage girl to take part in a role-playing game. “All of a sudden the girl said, ‘I suppose I could be happy,’ and became radiant, by choice, so we had done our job for the day,” he says.

“It’s the most nourishing, rewarding, and really transcendent joy I’ve ever experienced,” says Mandell, 34. “We just try to bring some shimmer into the room.”