EDMONTON — As his sobbing widow and one-year-old son looked on, Pte. Robert Costall's military family paid tribute to the fallen soldier during a memorial service Friday.

Costall was only 22 when he was killed last month during a vicious firefight with Taliban insurgents at a remote base in Afghanistan.

Tears streamed down Chrissy Costall's cheeks as camouflage-uniformed troops from the 1st Battalion, Princess Patricia's Canadian Light Infantry remembered her husband.

Maj. Rich Raymond likened Costall to a brave sheepdog, killed protecting a flock of innocent people from predatory, terrorist wolves.

"Rob the sheepdog rose to face the wolf," Raymond said as he stood before a picture of Costall taken in Afghanistan. The photo was flanked by the Canadian and PPCLI's regimental flag.

"In doing so Rob showed the love he had for his friends, because in facing the wolf, he laid down his life for them."

Pte. Ryan Fordyce, who grew close to Costall when they went through basic training together, told the hundreds of troops on hand at Edmonton Garrison that he will never forget his best friend.

Fordyce said Costall loved his family, friends, the military and hockey -- in that order.

Originally from Gibsons, B.C., Costall was known for his big smile and for being an excellent husband, father and soldier, he said.

"No matter what the situation, he was always eager and happy," said Fordyce, who recalled sharing a foxhole with Costall in bad weather during military training exercises in Alberta.

"It could be snowing in July in Wainwright or armpit-deep in a stagnant swamp. You could always tell where Rob was because you could see his teeth through his smile."

A few soldiers who were wounded in Afghanistan seemed to hang on every word spoken during the memorial service.

Master Cpl. Paul Franklin, who lost both his legs in a suicide bomb blast near Kandahar last January, struggled to stand to attention from his wheelchair on his new artificial limbs as a bugler played the Last Post.

With his wife Audra supporting him with her arm around his waist, the young medic, who has a six-year-old son, saluted Costall.

"I didn't know Costall, but when you're with this organization you respect everyone around you," Franklin said later.

"You have to respect what happened. Thank you for being a soldier. Thank you for being the Canadian that you were."

Also looking on was Warrant Officer Ray Brodeur, Costall's deputy platoon leader. Brodeur was shot in the leg and side during the same battle that cost the young man his life.

Brodeur said he will never forget that moonless night in March when the platoon was choppered in to help defend the remote base under attack from Taliban fighters.

He said he still recalls the mortars, rocket-propelled grenades and automatic-rifle fire that turned that night into horrifying chaos.

"This means a lot to me. Pte. Costall was one of my soldiers," said Brodeur as he leaned on a crutch.

"It was important for the regiment to recognize the sacrifice that him and his family made. It meant a lot to see that recognition and to ensure his sacrifice is not forgotten."

The military is investigating the possibility that Costall's death may have been the result of friendly fire.