Sudbury - As the Transportation Safety Board looks for the cause of a small plane crash that killed four people, two Sudbury families gathered on Thanksgiving Monday to mourn their loss but also give thanks for the lives of their loved ones.

Kevin Houle and his wife, Lorraine, both 50, joined by their 17-year-old daughter Emily and her boyfriend Michael Rollins, also 17, were on their way home for Thanksgiving Saturday night after visiting Emily's older sister Amber and stepsister Jacqueline in Kingston, Ont.

Conrad Houle, the family patriarch, said he is still in shock and cries when he sees his 19-year-old granddaughter, Amber.

"She lost her mother, she lost her father, and she lost her sister," he said from his family filled Sudbury home Monday.

"She is an orphan."

Kevin Houle, a licensed pilot, was flying the Piper PA-28, a four-seat, single-engine plane, which was registered to his family's mining business, Tracks and Wheels.

Houle said he believes his son ran into a "catastrophic" wall of weather.

"I suspect what happened was he got a good weather report when he left, and maybe half an hour into his flight he flew right into a wall of fog and rain and everything."

"And when you do that it could be catastrophic, and that's what it was."

Transportation Safety Board investigators believe it is unlikely the crash was caused by a mechanical failure and are looking into the role of a weather system in the area that night, board spokesman John Cottreau said Monday.

The plane was substantially broken when investigators arrived Sunday at a densely wooded area of Algonquin Park accessible only by helicopter or airplanes.

Cottreau said the wings were broken, the engine had separated from the body of the plane, and the propeller was separated from the engine.

Investigators determined the plane hit a tree at a high speed, meaning the engine was working and the plane was being flown -- it was not out of control.

TSB investigators removed the plane's log book and GPS unit from the wreckage for examination and are looking for air traffic control tapes, aircraft service files and flight plans to assist in the investigation.

Cottreau said the tapes could help to verify a witness' claim that a distress call from the plane indicated that rainy, foggy, and even icy conditions may have been a factor.

Conrad Houle said from the moment he received a call Saturday night saying that Kevin was 45 minutes behind his flight plan, he was on the phone with authorities all night.

The search and recovery effort was complicated by thick fog that forced a rescue helicopter to hover above the wreckage for three hours before it was clear enough to send a team down on ropes around 3 a.m., Houle said.

"They called me back 10 minutes later and said they found the wreckage and there was no sign of life. They were all dead."

Houle said his home was full of family and friends Monday, but instead of a Thanksgiving celebration, relatives came to grieve and offer support.

Houle said Kevin was excited when the family's successful mining equipment company acquired the Piper PA-28 airplane last year.

Kevin, who got his pilot's licence four years ago, flew to Montreal, Toronto, and often to Kingston to visit Amber and Jacqueline, who lived in a house together there, while Jacqueline completed a medical doctor internship and Amber studied physics.

Amber and her father were planning to leave Thursday for California, where she and other Queen's University students would compete in an aeronautics design competition for a half a million dollar prize.

"They thought they had a great chance of winning, but obviously she's not going down," Houle said.

The Rollins house in nearby Garson was also full of family Thanksgiving Monday, said Michael Rollins' grandmother Rev. Genny Rollins.

"We just want to make sure we love each other when we're here because you can't stop people from travelling or taking part in things they want to do," she said.

"We're just thankful Michael had a good full life for his 17 years."

Michael was well-liked by his girlfriend's family and had gone flying with them before, she said.

Michael's mother Sally and his two brothers liked Emily and were happy he was going on the family outing.

Rev. Rollins awoke to the news early Sunday morning, when she received a call from her daughter Sally.

"I couldn't understand who it was because she was so broken.

"I said 'who is this, you have to slow down and talk,' and she said 'Mom, it's me, it's Sally.

"'Michael is dead, please come'."

Rollins, whose All Saints Anglican Church is in Coniston, Ont., held a mass hours after learning of the death of her grandson.

"That was very hard to go through," she said. "But I really believe that even in our sorrow and grieving we have to go on doing things we've always done because otherwise we'll get cut off."

Michael and Emily, who had been dating for over a year, were both athletes and academics and were popular high school seniors with plans to go to university next fall.

"He just loved this girl," Rollins said. "They wanted to be with each other all the time, she said. "It was that young love that's so precious."

The Houle family is holding a triple funeral Saturday at the biggest church in the area to accommodate the outpouring from the Sudbury community.