Eighteen-year-old Heidi Allen had to work Easter morning, 1994. Her shift as a cashier at the former D&W convenience store, now a Valero, started before 6 a.m.

Heidi's sister, Lisa, and the rest of her family were at home, preparing Easter baskets.

"Heidi was energetic, always smiling," said her sister, Lisa Buske.

That's a demeanor she carried with her to work.

In fact, Heidi wasn't even supposed to be working that day. She was filling in for a co-worker who wanted to spend the holiday with her kids.

"She always put her friends first; friends and family first," Buske said. "That's just the way she was wired."

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Richard Thibodeau was also at the store that morning, for a quick trip that would stay with him for the next 25 years.

Thibodeau would be one of the last people to see Heidi Allen. She never made it home to celebrate the holiday with her family.

Allen vanished without a trace — her car in the parking lot, keys and purse untouched, her family left waiting for her return.

"My phone rang, and I ignored the phone because I figured it was work calling me in early," Buske said. "My aunt yelled into the machine, 'Heidi is missing, get to the store,' and hung up."

Her family thought it was all a big mistake.

"I went dressed for work thinking this had to be a complete misunderstanding," Buske said. "It's New Haven. All the lights and tape, that's when it sunk in that it was real ... 'OK, where are my parents? They're with the sheriff.' "

Richard Thibodeau says he was back at home, and didn't know anything was out of the ordinary until he watched the news that night. He says he told his brother, Gary, and other family members about the missing girl.

And that's when Thibodeau says he inserted himself back into the Heidi Allen story.

Family members said Thibodeau should call police and let them know he was there.

"I said, 'geesh, I don’t know if I should do that,'" Thibodeau said. "But I did. I called and said I was there ... and they said they would send an officer down here to talk to me."

Investigators did meet Thibodeau, who told them he just met Allen that morning.

"There was nothing more I could tell them, because I didn't even know who the girl was," Thibodeau said.

It was the first of two conversations he would have with police in 36 hours.

"There were people everywhere and so much food, everyone brought their Easter dinners up," Buske said. "They canceled their dinners and changed their clothes and showed up at the fire department with their dinners, desserts, everything, and just said, 'what do you want us to do?'"

"Heidi was energetic, always smiling."

The second conversation between Thibodeau and police would come the next day, when he and other community members, including the Allen family, were gathering to help in the search for the girl who still hadn't come home.  

"No parent should have to close their eyes not knowing where their child is," Buske said.