In 2010, Tanya Zuvers and her soon-to-be ex-husband, John Skelton, were going through a nasty divorce. Their three young children were caught in the middle of it all, sadly, and it turned tragic.

Nine-year-old Andrew, seven-year-old Alex, and five-year-old Tanner, went to their dad's house for Thanksgiving in Morenci, Michigan. When the kids were not returned to Zuvers the next day, she called the police. Skelton was arrested, and an investigation began.

The three boys were never found, and Skelton's story kept changing. Originally, he said the kids were with a friend. Then, the dad said he had handed over the kids to an "organization" as a way to protect them from their mother. He claimed the Zuvers was abusing her own children, having already been charged with having sex with a 14-year-old boy in the '90s. Zuvers maintained that she never hurt her children.

"That has all been investigated," Zuvers said. "My stuff was gone through. My children come first. Always have, always will. My dream job was to be a mom, and it is the greatest job in the world. But to say that I abused my sons, (that) kills me."

Skelton was ultimately charged with unlawful imprisonment and parental kidnapping. The kidnapping charge was dropped, but the father pleaded no contest to unlawful imprisonment. At his sentencing, Skelton refused to tell the judge where his children were.

"For months I have asked you to return Andrew, Alexander and Tanner. You have refused to answer me truthfully," Lenawee Circuit Court Judge Margaret Noe told Skelton before sentencing him to 10 to 15 years, the AP reported. "Your explanations have been ridiculous, albeit more sad than anything else."

Michigan authorities said they were building a murder case against Skelton, with the police chief saying, "I believe that John Skelton murdered those boys." Charges against the father were never filed.

On the seven year anniversary of her children's disappearance, Tanya Zuvers still held out hope that her sons were still alive.

"I wonder, are they scared? Are they crying for me?" Zuvers asked. "It's so hard to imagine them hurting for me and not being able to do anything about it."

"As a police officer, you know, you're realistic," Lt. Detective Jeremy Brewer, who took over the case in 2013, said. "You have to be realistic because you've had cases that some are solved and some are not. On a case like this, with the magnitude, with the resources we have directed towards it, I firmly believe without a doubt that we will get some type of closure on it one day."

Now, just over seven years since Andrew, Alexander, and Tanner Skelton went missing, a breakthrough in the case has been uncovered.

In Missoula, Montana, a box of bones was found in an abandoned shed by a cleaning crew. Police were called to investigate the discovery, and what they found could be a huge piece of evidence in the case of the missing Skelton boys.

"Loose teeth, there was what appeared to be bone from a lower jaw, and others that were not as specifically described, but I would call them pieces of bone. There were also rocks, in this box," said Missoula Police spokesman Sgt. Travis Welsh.

Lab analysis confirms that the box contained remains of three children: one between the ages of 5 and 8, one between 6 and 10, and the third between 2 and 4 years old.

Missoula authorities are trying to keep speculation at bay, however, saying there's no direct connection between these bones and the Skelton boys.

"Nothing we've been able to connect them to yet," Welsh said. "The thing is, there are missing children all over the world. And the thing is, we don't know that this particular case is isolated to the city of Missoula."

"Further forensic testing has been requested by police in Montana that may provide more answers," the Michigan State Police said Thursday night in a statement. "Until this testing is completed and additional investigation by law enforcement in Montana occurs, it cannot be determined if these remains belong to the missing Skelton brothers."

According to neighbors, the man who occupied the property where the bones were found was extremely unpleasant.

"The tenants were dirty," a neighbor said. "It was an unkempt house. The yard was a mess."

Tanya Zuvers posted a statement about the discovery on her Facebook page.

What do you think happened to the boys?