A father of three known as a “big teddy bear” was gunned down in a Missouri sports bar over an argument about a dog’s weight — just days after burying his own premature newborn daughter.

Scott Beary, 43, of Winchester, was killed Wednesday at the Show-Me’s Sports Bar & Grill in Florissant, where Beary got into an argument with another man about the weight of a German shepherd, one witness told the St. Louis Post-Dispatch.

A friend of the unidentified gunman — who had not been charged as of Monday — told fellow bar customers that his dog weighed a whopping 290 pounds, prompting Beary to call the man out as a liar, according to witness Carl Leavy.

“[Beary] said, ‘I’m 325 pounds, I can’t even fathom a dog as big as I am,’” Leavy recalled.

The dog’s owner said he had the animal in his car and invited Beary to come with him to prove it, but Beary was distracted by phone calls at the time, Leavy said.

The dog owner and his pal — the gunman — then left the bar only to return a few minutes later. But the gunman “didn’t seem the same” and appeared agitated, Leavy said.

After paying his $7.45 check, he turned to Beary and said: “No hard feelings,” according to Leavy — but then allegedly called Beary a “fat [expletive]” as he rounded the bar to leave.

Beary turned around and confronted the man — saying, “Why would you say that?” — before Leavy said he heard four or five shots, with the gunman firing directly into the victim’s chest. Florissant Police Chief Timothy Lowery said the gunman was then disarmed and detained by other customers until police arrived.

Police have yet to confirm Leavy’s account, according to the newspaper, but prosecutors are working to file charges against the gunman, according to police records cited by the Post-Dispatch that show a 54-year-old man was arrested on suspicion of second-degree murder.

The newspaper did not identify the man, since he had yet to be charged. WSMV reports that St. Louis County Prosecuting Attorney Bob McCulloch said Monday there’s not enough clear evidence to determine whether the gunman acted in self-defense or as the aggressor despite more than 20 witness interviews.

Making the case even more complicated, according to the station, is the changing nature of self-defense laws.

“Defense is always a consideration we look at, but now there’s defense of others, who’s the aggressor, who’s the initial aggressor,” McCulloch said. “The way the law keeps changing with Stand Your Ground and where you can take guns and all that information, it’s going to take awhile to sort through this.”

The shooter is not believed to be a threat to any of the witnesses or the public, McCulloch said. Investigators are continuing to review surveillance footage from inside the bar and await the completion of toxicology tests.

“He may end up charged at some point, he may not,” McColluch said of the gunman. “We have time to go through everything thoroughly and check it against the various statutes that come into play on this. Not just homicide statutes, but defense statutes, self-defense, Stand Your Ground, everything that plays into that. Which in this situation has certainly complicated things.”

Meanwhile, Beary’s relatives were left planning his funeral just five days after the family buried his 11-day-old daughter, Jocelyn, who died of complications from a premature birth on Feb. 2.

“We put her to rest and we were all healing and now this happens,” family friend and colleague Jeana Sellenschuetter told WSMV. “So, we’re going to start all over again and we’re going to be in that same church that we were just inside on Sunday and it’s not fair.”

Sellenschuetter also created a GoFundMe page to help offset funeral expenses and to help Beary’s widow, Christy, raise the couple’s three teenage sons. The fundraiser had eclipsed $53,000 as of Monday.

“He was the salt of the earth,” Sellenschuetter said of Beary. “He was a teddy bear.”