HALIFAX -- A Halifax mother is relieved that someone has now been charged with her son's murder.

Nineteen-year-old Triston Reece was shot in July and on Friday a 40-year-old man was arrested and charged with first-degree murder.

Police have charged Kaz Henry Cox of Halifax and Reece's mother says the news comes as a relief to the family, but still leaves her with more questions.

"What's going through my head is why," said Dale Adams, Reece's mother. "I don't know the man that was charged with Triston's murder, I just need to know why, I just want to know why."

Reece was shot in broad daylight on Scot Street in Halifax on July 26. He later died of his injuries in hospital.

Halifax police arrested Cox at the Central Nova Scotia Correctional Facility in Dartmouth.

Police believe Reece and Cox may have had some acquaintances in common.

"It's still an ongoing investigation, and we are following up on all avenues and leads at this point," said Halifax Regional Police spokesman Const. John MacLeod. "We certainly haven't ruled out there may be additional charges, again, that's still an ongoing investigation, and we're looking at all possible avenues."

Last month, police added Reece's case to the provincial rewards program for unsolved homicides and crimes, but police say that didn't play a factor in today's arrest.

Adams says she can't thank the investigators enough.

"There are mothers out there who lost their children in this way that don't have answers, that are not going to get the justice that I am going to get," Adams said. "So, I am extremely grateful to them."

Adams credits her faith in God for keeping her strong as she grieves.

Just last Sunday, she dreamt of her son for the first time since his death.

"I had a dream that I was talking to one of the officers, his name is Dwayne, on the phone, and we were having a conversation chit-chatting about the day and how the investigation was going," Adams said. "At the end of the conversation he said to me, by the way Dale, we got them and today, when he called me, he didn't say that, he got to tell me that in person."

Cox will face a judge in provincial court Monday and Adams says she'll be there.

Halifax police say they have reason to believe there are additional people who have information about Reece's murder.

They're asking anyone who has not already spoken with police to do the right thing and come forward either by calling Halifax police or Crimestoppers.