Contessa Fitts talked often with her younger sister, Nicole Fitts — though not every day — so it was a shock to learn on April 4, 2016, that the 32-year-old single mother was missing.
“I just remember getting a text message from my [older] sister around the fourth of April asking me if Nicki was missing,” Contessa, 37, tells PEOPLE. “I responded to her and I was like, ‘No, I just talked to her a couple of days ago.’ “
She took to Facebook, where a friend of Nicole’s had written a startling post saying that she had disappeared.
Terrified, Contessa and her family spent four agonizing days searching for Nicole and her 2-year-old daughter, Arianna.
Four days later, they learned that Nicole’s body had been found in a San Francisco park, in a shallow grave covered by a piece of plywood bearing a strange symbol.
But their nightmare wasn’t over: Arianna was nowhere to be found.
“It’s devastating,” Contessa says now, as the third year approaches without answers in her niece’s disappearance or her sister’s killing.
San Francisco police classified Nicole’s death as a homicide. They have said they also believed that Arianna had been missing since February 2016 and characterized her as being “at risk.”
Nicole and Arianna both had ties to the greater San Francisco and Silicon Valley areas and regularly visited Southern California, police told PEOPLE in 2016.
Arianna was last seen in Oakland, according to authorities.
In May 2016, a Best Buy store in San Francisco, where Nicole had worked, announced a $10,000 reward for information in the case.
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Police tell PEOPLE they are still investigating.
But Contessa and her family wonder about a possible link between Nicole’s death and Arianna’s disappearance. “I think it’s absolutely connected,” she says.
Still, there is no trace of the little girl.
“Nothing,” says Contessa. “No one has heard anything. My mind is just boggled like, where could she be? Her picture has been out there so much.”
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As investigators seek clues in Nicole’s slaying and Arianna’s disappearance, Contessa and her family continue to hold out hope that they will one day find the girl with the sweet smile and gentle disposition.
“I’m trying to remain hopeful that she is alive,” Contessa says. “I can’t allow myself to think that she’s not.”
Anyone with information concerning Arianna’s whereabouts or Nicole’s death should call the San Francisco FBI at 415-553-7400.