A former security guard was sentenced to at least 50 years in prison on Wednesday after pleading guilty to fatally stabbing a Timberland marketing director at the outerwear company’s New Hampshire headquarters last year.

Eight family members of Catherine “Cassie” Heppner told the court how much they have missed her since her death on Feb. 9, 2020.

“I know I’ll never fully understand the pain I’ve caused,” Robert Pavao, 22, said in a written statement that was read in court by his lawyer as he sat shackled with his head lowered.

“I’m sorry from all my soul taking away one of your loved ones,” Pavao’s statement said. “I can’t imagine losing a sister, a mother, or a wife. … I hope one day I can be forgiven for what I’ve done.”

Heppner, 46, had worked for Timberland for over 13 years and was considered “a high performing talent with the potential to lead the company’s global marketing operation in the future,” according to a statement from a vice president of human resources.

Heppner had gone into the office on a Sunday afternoon to retrieve some product samples and finish up a presentation for a planned business trip to Dallas the next day. She needed access to a storage closet, but it was locked. Pavao, who was working that day, had the key.

Security camera footage shows both Heppner and Pavao going into the closet, and that Pavao closes the door at one point. After a half hour, Pavao is seen leaving the closet. Prosecutors said he was covered in blood. He called his mother and sister, said he had “blacked out,” and they told him to call 911.

Pavao, formerly of Berwick, Maine, originally was charged with both first- and second-degree murder and had pleaded not guilty to killing Heppner at the Stratham-based company.

He pleaded guilty to second-degree murder on Wednesday as part of a negotiated plea deal with prosecutors. The terms called for a prison sentence of 55 years to life, with five years of the sentence deferred for 20 years on conditions. A first-degree conviction would have called for a life sentence without the chance for parole.

A lawsuit filed in federal court against Securitas by Michael Cormier, Heppner’s husband, says that the company negligently hired Pavao, despite alleged “red flags” about his psychological state. It said he allegedly used marijuana and psychedelic drugs at work, and allegedly had mental breakdowns at work that went unreported by a supervisor.

In its response, Securitas said it bears no responsibility for Heppner’s death. Securitas said it didn’t cut any corners in hiring Pavao, and that it didn’t receive any reports concerning him and the alleged drug use. Securitas also said no employee reported any troubling information about Pavao.

Nothing at Wednesday’s hearing was discussed about Pavao’s state of mind at the time. Much of the hearing was devoted to family members who wrote and spoke of Heppner’s infectious laugh, her work ethic and her kindness.

“I feel sad that I will not be able to see Mom again,” Heppner’s 10-year-old son, Jack, said in a statement read by a family member. “I can no longer ski with Mom, which is something that we did together since I was barely walking. I can no longer go to the lake with Mom. I miss the days hiking at Sunday River with Mom,” a ski resort in Newry, Maine.

When asked what he’d like to see happen to the person who took his mom’s life, Jack wrote, “I think he should be in jail for the rest of his life so he cannot hurt anyone else.”

Rockingham County Superior Court Judge Daniel St. Hilaire called what happened a “senseless and brutal act,” and said to Pavao, “I don’t know why you did what you did. Nobody will ever know.”

He said Heppner’s family came to court to express their remorse, anger and hurt.

“I want you to keep their words in mind for the rest of your life,” he said.