It was an unseasonably warm February afternoon in 2017 when Kelsi German dropped off her sister and a friend at an abandoned railroad bridge near a popular hiking trail for a favorite pastime – snapping photos of each other walking along the historic 63-foot-tall Monon High Bridge in Delphi, Indiana.

The girls never made it home alive.

Liberty German, 14, and Abigail Williams, 13, were found murdered the following day in a case that shook a small Indiana town and left law enforcement unusually tight-lipped in their hunt for a killer.

Now, five years later, German’s grandmother said a man who communicated with the girl through a fake social media profile may "know more than he’s saying" and called on the public to come forward with information on the account allegedly used to solicit nude photos of underage girls.

Libby German and Abigail Williams

On Feb. 14, 2017, Libby German, 14, and Abby Williams, 13, were killed while biking on trails near Delphi, about 60 miles northwest of Indianapolis. (Indiana State Police)

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"I have seen where he did comment on Libby's page," Becky Patty, the girl’s grandmother, said in a lengthy sit-down interview with Fox News. "I know for a fact that this ‘Anthony_Shots’ account did have contact with Libby."

Kegan Anthony Kline, 27, of Peru, Indiana, allegedly created the Instagram account known as "Anthony_Shots" to communicate with underage girls but denied any involvement in the murders. The profile, which was active from 2016 to 2017, used real photos of a male model from Alaska to "catfish" unsuspecting girls and solicit sexual photos and videos.

Kline was charged in August 2020 with 30 counts, including child exploitation, possession of child pornography and obstruction of justice. He has not been charged in the murders of German and Williams nor been named a suspect. In March, a transcript of a video interview Kline gave at an Indiana State Police barracks was accidentally posted online and obtained by "The Murder Sheet" podcast. 

According to the document, which has since been sealed in the court record, Kline told police he communicated with German on the day she was killed. The transcript also revealed that Kline searched "How long does DNA last" on his computer and failed a police polygraph.

Investigators reportedly told Kline that they believe at least two people had access to the "Anthony_Shots" account based on the forensic investigation into the syntax, or wording, used by the account. According to the interview transcript, Kline said he gave the account password to "a lot of people."

Kegan Anthony Kline

Kegan Anthony Kline has not been named a suspect in the murders but said he communicated with German on the day she died. (Miami County Sheriff's Office)

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Police said German used her cell phone to snap images of a man walking across the railroad bridge shortly before the girls were killed on February 13, 2017. German also recorded the man believed to be the killer ordering the friends "down the hill."

While much attention has been given to the phony "Anthony_Shots" account, Patty cautioned against focusing solely on one individual in the investigation and disclosed that police recovered DNA at the crime scene, though she did not provide any details.

"I can't go down just this one avenue," Patty said. "I still have to keep an open mind that it was something else.

"In America, you're innocent until proven guilty. No matter what the evidence is there, no matter what is insinuated. Even though he [Kline] is facing these other charges, he's innocent until proven guilty."

Vincent Kowalski, whose images turned up in the fake profile, now responds.

Vincent Kowalski, whose images turned up in the fake profile, now responds.

Meanwhile, the former male model whose images were allegedly used by Kline said he is sickened by the murders of the girls.

In an email to Fox News, Vincent Kowalski, now a police officer in Alaska, said, "My condolences are with the families of those girls, and will forever be disgusted by what happened to them.

"The only thing I want to do is have the individual found and prosecuted to the fullest extent of the law. I hope my brothers and sisters in blue who are hard at work on this case will get the break they are looking for. I only wish I could have been there to protect them."

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For 22-year-old Kelsi German, the last image of her younger sister — carefree and smiling — is forever frozen in time.

"I remember us just being so happy in the car and listening to Twenty One Pilots and the windows were open, and it was just so warm. And she got out of the car and told me she loved me," German said. "I’m glad I got to hear that one more time."