EVERETT — During the holidays, Donald Barker told his family he wanted to coach his son’s soccer team. A former semipro player himself, he rode his bicycle to every one of his son’s practices.

Barker also told his sister he wanted to learn to play bass guitar.

His family is just grateful they had him for Christmas.

Only two days later, Barker, 37, of Everett, was found fatally stabbed at Madison Elementary School on Pecks Drive west of Evergreen Way.

On Wednesday night, Everett police arrested a man in connection with the killing. The man, 44, of Everett, already was in custody on an unrelated warrant. He is now being held as well for investigation of second-degree murder, Sgt. Robert Goetz said.

The break in the case came when a woman, whom police had interviewed early in the investigation, agreed to again speak with detectives. This time, she talked about how the suspect had brought a knife to her home and asked her to hide the weapon, police said. The suspect also demonstrated how he and another person beat and stabbed Barker. A third man was said to have been present, but only as a driver.

Police on Wednesday couldn’t say what the motive was for the killing, but it was not a random act, Goetz said.

Barker’s family held a candlelight vigil and memorial ceremony for him over the weekend, said his aunt, Jennifer Schorr. The memorial at the funeral home was standing-room only.

It is difficult to come to terms with his death, she said.

Barker had struggled with a drug addiction for several years, said his mother, Beth Piasecki.

So often, he would get clean, get a good job and start doing really well.

Then, once or twice a year, he would go on a drug binge and lose everything, she said.

Barker hated his addiction, Schorr said.

“He wanted recovery and just couldn’t get it,” she said.

Barker never let drugs get in the way of being a father, Piasecki said. He adored his son, who was his whole world.

“He was just an all-around good person who had a disease,” Piasecki said.

The family said they know Barker was clean while spending Christmas with his son.

They don’t know if his killing was somehow drug-related, but said Barker was overdue for a relapse.

Regardless, his family won’t remember him for his addiction.

They remember a man who banged on doors during an apartment fire to save strangers’ lives. They remember a man who nursed a dying relative at home for months. A man whose grandmother was his best friend.

Since Barker’s death, they’ve heard from hundreds of people who knew him. They are overwhelmed by how many lives he touched, they said.

They are planning a private cremation ceremony for him today. They plan to bury half of his ashes with his little sister, who died as a toddler. The other half will be scattered this summer at the family’s favorite campsite along Wiley Creek east of Verlot.

Barker’s happiest times were during the semiannual camping trips at Wiley Creek, his mother said.

Can you help?

Everett police urge anyone with information about the stabbing to call the tip line at 425-257-8450. Crime Stoppers of Puget Sound also is offering a reward of up to $1,000 for information leading to an arrest and filing charges on any suspect or suspects in the case. Their number is at 800-222-8477.

Barker’s family is offering an additional $500 reward for information leading to an arrest and conviction.