As search continues for missing Chelsea man, family of his late girlfriend also seeks answers

Where is Juan Santiago, the 35-year-old Chelsea man last seen in Texas in June?

And what really happened to his girlfriend, Kristina Mock, who suddenly died before she could talk to police?

These are questions haunting two Massachusetts families struggling to find answers.

Sara Kulmacz is the mother of Juan Santiago’s two teenaged children. She believes the truth might be slipping away.

“I don’t think we’re going to get all the answers, unless there is somebody else involved,” Kulmacz told me.

Juan Santiago vanished from a Motel 6 on June 19, about 12 hours after he and his girlfriend, Kristina Mock, took a train from Boston to San Antonio, Texas.

>> Family of missing Chelsea man fear they may never find him

Juan told his family he had a friend in San Antonio who could help him land a job so that he and Kristina could start a new life.

Just before Juan disappeared, he called 911.

This is an edited portion of the call:

Santiago: “I’ve got a situation where I live at.”

911: “Yes sir.”

Santiago: “If you could track the phone down from where it’s at right now, you’ll know where I’m at. The situation is you know, I had somebody, you know come here and try to rob me and all kind of things. Please can you send somebody here?”

911: “Yes sir.”

Juan was never seen again.

When Sara found out Juan was missing, she flew from her home in Florida to San Antonio to look for him.

Kristina Mock came too.

Sara claims Kristina first told her that Juan was suffering alcohol withdrawal and was experiencing hallucinations and that he ran out of the hotel room.

But later, Sara heard the 911 call, and now she suspects Kristina knew more than what she was saying.

“I felt betrayed. I wish she just told me the truth from the beginning. Because I would have had more to go on when I went out there,” Sara said. “I would have been looking harder in wooded areas, for body and not just a homeless man.”

But Kristina’s family has questions, too.

A close family member told me that Kristina told him, Juan was suffering alcohol withdrawal on the train even before they got to Texas.

And he added, he wants to find Juan Santiago as much as Juan’s family.

On July 13, Kristina Mock wrote an emotional birthday message to her missing boyfriend on Facebook, saying in part “I miss you more and more every day. I love you so much.”

But two weeks later, Kristina was gone too.

On July 26, Kristina Mock unexpectedly died at Melrose-Wakefield Hospital, the day after she checked herself in.

Juan’s family says Kristina told them she was having suicidal thoughts and wanted to get help.

Kristina Mock was planning to talk to Chelsea Police about what happened in Texas.

But now Kristina’s family is questioning what really happened to her. They are devastated.

And Juan’s family is heartbroken, too.

They are wondering if they lost the best chance they had to find out what happened to Juan.

“She was the missing piece to the puzzle. She knew exactly what happened that day, when Juan went missing. Unfortunately, we’ll never get that piece anymore. We’ve had to accept that at this point,” Sara told me.

Another search for Juan Santiago in Texas is being planned.

In the meantime, if you have any information about what happened to him, call Chelsea Police.

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