Kimberley RCMP Cpl. Chris Newel said the two men, both in their fifties, were enjoying their long weekend at Whiteswan Lake when a vehicle crashed through the forest and plunged into the water.
A mother had been driving her 16-year-old daughter and five-year-old son along a forest service road toward a number of campsites when she lost control, Newel said, and the vehicle headed straight into the lake.
The mother and daughter were able to escape and swim to shore, but Newel said the son remained trapped in his car seat as the vehicle sank to about two metres below the surface.
The brothers, from Lethbridge and Turner Valley, Alta., immediately jumped into the lake and swam to the boy's aid. After several attempts, they finally managed to free the child.
"There was a multitude of things that came together at the right time to have a good ending to this," said Newel, adding the outcome likely would have been tragic if the brothers had not been there.
Newel said a few other people also need to be credited with the boy's rescue, as they performed CPR on him when he was pulled to shore and got all three of the vehicle's passengers to hospital.
The five-year-old is reportedly doing well, but several medical tests still need to be performed before he is released. Newel said the mother and daughter suffered no notable injuries.
The RCMP are still investigating why the mother lost control of the vehicle, and brought in an analyst to do a scene examination.
However, Newel said they may "never know the exact reason."
"It's your typical gravel forestry road," he said. "It's fairly easy to lose control in those types of situations."
Newel said the vehicle has already been pulled from the lake.
-- By Kim Nursall in Vancouver
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