GRAPEVINE (CBSDFW.COM) – A mother and son who were pulled out of Lake Grapevine last week have died.

The fire department said the mother saw her son – 13-year-old Aiden Rock – struggling in the water last week.

But when she went in to help him, she ended up needing help, too.

Neither the mom nor her son were wearing life jackets.

“Again, no life jackets,” said Assistant Fire Chief John Sherwood the day it happened. “We can’t stress that enough that wearing a life jacket when we’re in and around water is imperative for your safety.”

Four people have died in Grapevine Lake since Mother’s Day, which is double the amount of drownings there in 2017.

At least six people have drowned at Lake Grapevine since May.

“You need to have a plan when you go to a body of water, just in case something tragic happens,” James Fike said Monday.

As a swim coach, and president of the Fort Worth Drowning Prevention Coalition, Fike said life jackets are still the best plan for open water. The group however, is also teaching children and adults how to safely respond when someone in the water needs help.

“If you go to rescue somebody, they’ve lost all reason,” he said. “They don’t care that you’re a loved one, a family member, brother sister, mother, daughter. Their only thought is survival. And they will push you down under for that extra bit of time it buys them to stay above the water.”

Fike said they teach “Throw, Don’t Go.” Throw something buoyant into the water, rather than go in after them. It can be difficult to fight the instinct to just jump in, he said, but it’s necessary.

“You have to have your wits about you and think about yourself. You’re not doing them any favors, by also drowning.”

The coalition was starting a two-week Swim Safe program Monday night at the Eastside YMCA in Fort Worth. The classes provide instruction both in and out of the water, on safety skills and using life saving equipment.