Jeffrey Mueller knows firsthand the sacrifices of serving in the military.
"I deployed over 19 times," says Mueller, a retired U.S. Navy Chief Hospital Corpsman. "I was in combat twice."
Mueller is giving back on September 11th, a day that touches close to home.
Habitat for Humanity has teamed up with The Mission Continues, a veterans organization.
"We're out here on September 11th repainting a building that is in the historic district of downtown Frederick for the revitalization project," says Ron Cramer, Executive Director of the Frederick County Habitat for Humanity.
"This is a positive activity that we can do to commemorate the sacrifice that many, many, many people have been as a result of what happened on September the 11th," says James Fetig, Chief of External Relations for the Corporation of National and Community Service.
Sparky is Jeffrey's service dog. The two-year-old yellow lab helps him readjust to civilian life after 21 years of service.
"I've had a lot of doctors. I've been on lots of medications, and there has been nothing that has helped me as much as Sparky has," says Mueller.
Sparky even wears some of Mueller's Navy badges on his service vest.
"My mission now is to continue my recovery, get my education, and give back what has been given to me," says Mueller.
Mueller's also giving back to his community by leading this revitalization team with his best friend Sparky next to his side.
He plans to graduate with a Master's degree in 2014 and wants to get his clinical license to help other veterans' transition to life as civilians.