Police and volunteers spread across Saskatchewan’s Echo Lake Tuesday in a desperate search for a missing seven-year-old boy.

The search for Greagan Geldenhuys began Saturday after the body of his mother, Tamaine Geldenhuys, was discovered at the lake, which is approximately 70 kilometres northeast of Regina.

“(We’re) just looking for him, hoping to find him OK,” Greagan’s older brother, Ryan Geldenhuys, told CTV Regina from the scene. “But nothing less, we just would like some closure.”

Standing alongside his sister, Corrinna Howard, he said that they believe their mother and brother were involved in a swimming accident last Friday.

“(They) just went to the beach for a fun day and things took a turn for the worse,” he said. “That’s all we can really think of right now.”

Tamaine and Greagan lived in the nearby village of Lebret, where Tamaine helped others in the community as a wellness instructor. She grew up in the town of Fort Qu'Appelle, which sits alongside Echo Lake.

“Our mom was very loving,” Ryan Geldenhuys said. “And Greagan is a very caring and mature young boy.”

On Tuesday, an RCMP dive team waded through waist-high water as they searched sections of a beach on the east side of the lake. By the afternoon, a private plane and hovercraft had joined the effort. More than 50 volunteers from Standing Buffalo Dakota Nation, which sits on the lake’s western shore, have also been helping since Monday night.

“Like anything else, when you have a report of a child that’s out there, potentially within the area somewhere, we all just have to come together,” Brian Kishayinew told CTV Regina.

Conditions on the lake were windy and cold Tuesday, hampering search efforts.

“The water’s kind of murky,” family member Rob Nelson, who is helping with the search, said. “It’s difficult to see down deep into the water, so we can pretty much see the surface and maybe about three feet below.”

The search will continue Wednesday.

With a report from CTV Regina’s Creeson Agecoutay