SAND SPRINGS, Oklahoma - A Tulsa teen drowned on Thursday as he tried to help rescue his friends who were struggling in the water at Keystone Lake.

A Sand Springs woman jumped in afterward and helped save one of the girls.

The body of Brendan Earl, 18, was recovered in 8 feet of water at Lake Country Swim Beach three hours after he went under.

Holly Lewelling was able to pull Makia Graves, 17, and Kayla Barnett, 18, back to shore. Lewelling administered CPR on Barnett, which investigators say saved the girl's life.

Barnett and Graves are said to be in good condition at a Tulsa hospital.

"She had a pulse rate," Lewelling said. "I felt that and I saw her chest start coming up and I went like this and pressed in and it was just water."

It was the first time she'd performed the rescue technique on a human.

"I've been doing this, the CPR, working with kids for eight years on dummies, but I've never done it on a live person until this happened," she said.

According to a report by the Oklahoma Highway Patrol, Graves was riding Barnett's shoulders when Barnett waded into the water. Barnett stepped into a drop-off, which caused Graves to start struggling and Barnett to go under, OHP said.

That's when Earl jumped in the water to help and drowned in the process.

Lewelling was in the right place at the right time.

"It's my duty; I feel like it's my duty," Lewelling said. "If I see somebody down here - it doesn't matter where - it's my job as a person who's trained to get down there and make sure everything is okay."

She may be trained, but witnessing such a tragedy tugs at her heart.

"I woke up this morning crying. The kids' family, my heart goes out to them," she said. "I feel great that Kayla is alive and she's doing okay. My heart goes out to her, because of her loss with her friend and also the kid who lost his life out here."