DENVER – On Monday morning, Christopher Watts — the man who pleaded guilty to killing his pregnant wife and two daughters — will learn his fate in court in Greeley.

Shanann Watts’ family will be in court as well and will face their loved ones’ killer.

There are few people who personally know the pain of losing a loved one in such a sudden and sinister manner, but Tom Sullivan is one of them.

His son, Alex, was shot and killed in the Aurora theater shooting about six years ago.

“It’s a lifelong emotional roller-coaster of trying to mend a broken heart and trying to find some way to fill the soul that is leaking out of you every day,” Sullivan told FOX31.

There’s not a day — much less an hour– that goes by that Sullivan doesn’t think of Alex.

“Sometimes, I’ll say something and I feel myself getting emotional. And it’s like, jeez — I should be able to talk without getting emotional, but it’s like, no, no. It’s OK,” he said.

Sullivan is talking about this now because another family, Shanann Watts’, is fraught with that familiar heartbreak.

However, they won’t have to agonize through a weeks-long trial as Sullivan did.

Christopher Watts pleaded guilty to three murder charges for the deaths of Shanann and daughters Celeste and Bella. Along with other felony counts, he faces the possibility of multiple life sentences.

His criminal case is quickly closing, but for Shanann Watts’ family, that doesn’t necessarily mean closure.

“That whole part when people say, ‘I just want to get over this…’ well, my response to that is: You’re not going to get over this,” Sullivan said.

It’s Tom Sullivan’s life lesson for Shanann’s family and others who have have had a loved one killed.

Watts’ sentencing beings at 10 a.m. Monday. FOX31 and Channel 2 will have full coverage on air and online.