A boy who survived an accident that claimed the lives of his mother and six-year-old brother has spoken almost a year on.

Lucas and Samuel Walker were swept out to sea by a wave during a visit to Aberdeen beach on August 20 last year.

Their mother, Julie, leapt in after them but also got into trouble in the churning water.

Julie and Lucas did not survive, while Samuel, then 13, was rescued with hypothermia.

Nearly a year after from their deaths, Samuel still struggles with the events of that day.

"It's terrible, you just want to see them again and hear them again, it still hurts," the 14-year-old said.

Julie, Lucas and Samuel had gone shopping near the beach to stock up on supplies for a dog they would pick up the next day.

"We were down at the beach the week before and we had buried Lucas in the sand," Samuel said

"He loved it so he asked to go down."

After arriving at the shore the trio made their way down a ramp at the edge of the water, where they stopped to take a picture.

"A couple of waves were hitting beside the ramp but we didn't think much of it," Samuel said. "We got hit by a wave and Lucas was laughing.

"Then a second one hit and we both went down. I couldn't keep hold of Lucas and he disappeared."

Julie, who was still on the ramp, jumped into the water after her boys but immediately got into difficulty.

"All I can remember is being hit by a wave and being stuck under the water," said Samuel.

Realising they were in trouble, passers-by threw life rings into the water.

Julie, 37, and Samuel were able to grab hold of one but Samuel became tangled in the rope.

"Mum couldn't hold on and she got swept away," Samuel said.

"They kept on trying to pull me up and as I was being pulled up I saw mum upside-down in the water."

Samuel was taken to hospital with hypothermia, along with a man and woman who had jumped into the water in an attempt to rescue them.

"In the ambulance they were telling me everything was fine," he said.

"But I was saying what I thought - what I didn't want to be true - that my mum and Lucas had passed away."

Lucas and Julie were buried alongside Julie's twin Laura-Anne, who died of meningitis aged five.

Samuel's older brother, Jordan, said he thinks about the accident every day.

"Every time I go to sleep it hits me," the 17-year-old said.

"Even when you're working, even when you're not thinking about it it's always there.

"I wish I was there to help. What if I was? It feels like it wasn't supposed to have happened. I sometimes wake up in the morning thinking I'm at home but I'm not."

Samuel and Jordan have been taken in by their grandmother, Lynne, and her partner Keith.

Samuel said the experience has made him more determined to succeed in life and make his family proud.

"Lucas was a very smart boy so I'm trying to be even smarter, get good grades, a good job and make a good future for everybody," he said.