A young mother in Missouri, eight and half months pregnant with baby number two, leaves church to meet up with the man she says was the father of that unborn baby. She would never been seen again.

Bryan Westfall has become pretty well-known around Festus, Missouri for not wanting to talk to anyone. At least not about Amanda Jones, a young woman who claimed she was carrying his baby before she suddenly vanished 11 years ago.

And Westfall, the last-known person to see Amanda Jones, before she disappeared has maintained a vow of silence about the case all this time, except for an initial interview with police.

"He cooperated at first and was interviewed by two detectives with a lawyer present," said Jefferson County Sheriff's Lt. Eugene Coombs.

Amanda Jones was a 26-year-old divorced single mom who worked at a local bank and was well-loved by everyone who knew her in the rural community of Festus, Missouri. Her daughter, now 14, was only four years old when Amanda went missing on August 14, 2005.

Amanda became pregnant with a baby she said was fathered by Bryan Westfall, a local farm boy she dated very briefly after meeting him at an office Christmas party at the local civic center, where he was a volunteer worker.

"When she told me about it I was a little shocked, and I asked her 'How do you feel,' and she goes, 'I'm happy about it. It's a little surprising, but I'm happy, you know. I'm gonna have another baby. I'm excited,'" said Amanda's sister, Carrie Alfred.

Amanda's family members were just as thrilled as Amanda. But reportedly not so excited was Bryan Westfall, who already had a longtime girlfriend.

"He told her it's not his, but he would pay for her to have an abortion," said Bertha Propst, Amanda's mother. "She said, 'I don't believe in abortion. I'll raise this child on my own.'"

Amanda's family says she began preparing for the arrival of her baby, which she had learned was a boy, and had already named Hayden. When Amanda was eight and a half months pregnant and the big day was fast approaching, Amanda's mother says her daughter reached out to Westfall again.

"And wanted to know if he changed his mind about having a relationship with the baby," said Bertha. "She was going to give him one more chance, and as far as I know he said no."

But a short time later, Amanda's family says she got a surprise Sunday morning phone call from Westfall asking if he could meet to talk about the baby, and then go to lunch at a restaurant called Off The Hook.

"And she said it would have to be after church," said Amanda's father, Hugh Propst.

As planned, Amanda left church to go meet Westfall at the civic center at 1 p.m. on Aug. 14, 2005.

"She kissed Hannah and she told her 'Mommy will see you in a couple of hours,'" said Bertha.

But Hannah would never see mommy again.

"A couple of hours had gone by and she wasn't home, and we all kept calling her, you know, kept calling her cellphone and kept getting voicemail," said Amanda's sister, Carrie.

Carrie went to Amanda's home, but she wasn't there, and the family starts getting worried. Amanda's former sister-in-law Rhonda Willis had called her at 1:16 p.m., shortly after she was to have met with Westfall. And she was taken aback by Amanda's response.

"She answered very abruptly, and it was so abrupt I didn't really know if I had Amanda or not," said Willis. "And she said 'I can't talk right now,' and that was really unusual for her because she never, ever had talked to me like that."

Mom Bertha calls Bryan Westfall.

"He says 'Yeah, we met, we went to lunch, then I dropped her back at her car at 2 o'clock," said Bertha.

But Bertha says Westfall called back to admit he and Amanda didn't go to lunch like he'd said.

"And he says 'I met with Amanda. She got upset. She wasn't hungry. I wasn't hungry. She used the bathroom and I left her at 2 o'clock and she was still on her phone,'" said Bertha.

"He called us about three times after the initial phone call, and every time it was a different story," said Hugh Propst, Amanda's father.

Finally, family friends check the civic center parking lot and find Amanda's car -- with no Amanda in it.

Amanda's family reports her missing to police, who search the car to discover her purse and cellphone are not there.

But Detective Doc Coombs of the Jefferson County Sheriff's Office is quickly convinced Amanda didn't just up and disappear of her own volition. Bryan Westfall is asked to come to the station for questioning, and takes Detective Coombs by surprise when he turns up with an attorney.

"To me it's odd that a person would pay for a lawyer when they don't need one," said Coombs. "If he thinks he needs a lawyer, that's fine, but to me he's just a witness like any other witness."

Westfall tells detectives what he had told Amanda's parents: that he had spoken with Amanda about the baby for about an hour in the civic center parking lot.

"According to Mr. Westfall's initial statement, Amanda alluded to the fact that she was currently receiving $600 a month child support from her ex-husband, and she implied that might be the amount of child support for her expected baby," said Coombs. "He doubted he was the baby's father. He questioned that."

Westfall tells detectives that it was a civil conversation.

"They really didn't decide on anything or agree on anything at that time," said Coombs. "Amanda went to her car, and according to Mr. Westfall she started it, and that's the last time he saw her."

But Westfall had also told detectives and Amanda's parents that he drove through the civic center parking lot three hours later, at around 5 p.m., and saw Amanda still sitting in her car with a cellphone to her ear.

And detectives say cellphone tracking records reveal she hadn't made or received a call since that disturbing conversation with her former sister-in-law.

There is still no evidence after 11 long years of searching by police, hoping and praying by friends and family, and offers of large rewards.

And all this time Westfall's attorney has not allowed him to speak with any investigators, including FBI Special Agent Mike Christian, who was assigned to assist with the case when Amanda's disappearance was declared a suspected kidnapping.

"He was the last person to see her. So obviously whatever information he has we are interested in," said FBI Special Agent Mike Christian.

Crime Watch Daily tried to get answers for Amanda's grief-stricken family, and sought out Bryan Westfall at his family farm. His parents told Crime Watch Daily to speak with Westfall's attorney.

Bryan Westfall has never been charged in connection with Amanda Jones's disappearance.

"I think it's an extremely solvable case," said Mike Christian. "I think someone is going to come forward and I think we're going to get the information we need."

If you have information related to Amanda's disappearance, contact the Jefferson County Sheriff's Department at (636) 797-5515.

August 31, 2018: Parents of Amanda Kay Jones still searching for daughter thirteen years after her disappearance - NBC News