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A father shot his estranged wife to death and then killed himself during his daughter's 16th birthday party, police said.

The shootings happened outside the front door of the teen’s grandparents’ house in Grapevine, Texas, late Saturday.

Kristi Suckla, 44, had moved to her parents’ house with her teenage son and daughter after the couple separated.

Grapevine police said her husband Kelly Suckla, 43, came over to the house Saturday night for the birthday party.

An argument broke out and investigators said Suckla then shot and killed his estranged wife with a handgun before taking his own life.

The children and grandparents were inside the home and were not physically hurt.

The couple previously lived in Euless, Texas. Neighbor Donell Arseneau took the news with tears.

"They would just come over and we'd visit and I'd been over there a few times," Arseneau said. "They'd have little parties on the weekends. They had just recently separated. Kristi hadn't been staying over there (at her parents) but for just a few weeks."

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Arseneau said they had recently celebrated their 20th wedding anniversary.

"They just got along so well so even when she moved to her parents, I just figured she'd be back in a little while,” she added.

Grapevine police detectives said they were continuing their investigation but called the deaths a murder-suicide.