Deputy Debbie Callis has served Suffolk for 21 years, but she’s helped the American Red Cross ever since she was a child.

Her father had heart complications during her childhood, including a triple bypass at age 35. Callis gave blood in his name then, and she continues to do so now after his death.

She has a tattoo on her left arm that reads, “You know how much I love you, Dad.” It’s in her father’s handwriting.

“It was the last card he sent to me before he passed,” Callis said.

An American Red Cross bloodmobile parked next to the Suffolk courthouse on Monday was taking blood donations, and people like Callis helped save lives across the country in desperate times.

The mobile unit was available for just a few hours, staffed with three people and a goal of at least 10 donations. They received 12, and only three of them were appointments.

Most of the volunteers heard about the blood drive through the Suffolk Sheriff’s Office and were able to attend thanks to the blood drive’s convenient location.

“I do it whenever I can, but when it’s right outside our building, I don’t have to go hunting for one,” Callis said.

A donation can take up to an hour and 15 minutes from the moment a volunteer walks through the door. Each person gives a pint per donation, and a healthy donor could contribute every 56 days.

Jonathan Kent, a 61-year-old retiree and a Red Cross volunteer for years, is one such contributor.

“I try to do it every 56 days,” Kent said. “I just like to give and help somebody. You never know when you might need it.”

The American Red Cross estimates that of the 38 percent of Americans eligible to donate, less than 10 percent of them do so each year. The Red Cross has identified a national blood supply shortage in recent months.

The Red Cross accounts for about 40 percent of the nation’s blood supply, and 80 percent of that comes from bloodmobile donations. The organization is calling for more donors, sending out emails and organizing blood drives across the country.

“Put yourself in that situation when you may need blood,” Deputy Ron Whitley said.

Whitley said if that were the case, you would want it to be stocked.

To learn when and where you can donate, visit www.redcross.org.