Adriana Davidson missing: Ann Arbor, MI family searching for teen gone for days; foul play suspected

ANN ARBOR, Mich. -- With tears in their eyes, brothers Anthony Lopez and Michael Sugano and father John Davidson, all huddled together Sunday afternoon to call out for their missing sister and daughter, 15-year-old Adriana Davidson, or as they call her, Addy.

"She is super super smart, like disgusting smart. She was 7 years old with cardboard and scissors building arms," Lopez said. "She just has this unconditional love for animals, and she has her cat here and I know she misses them like we miss her and ... we just, we are thankful for everyone who is sharing."

Davidson said he last heard from Adriana Davidson when she left for school at Pioneer High School in Ann Arbor Friday morning. She takes Ann Arbor public bus "The Ride."

When she didn't come home that afternoon he called and texted her. She always responds to him, but Friday she did not, WXYZ reported.

"We're going on what, day two now? This is not my daughter," Davidson said.

"So there's definitely some suspicious pieces to this," said Derrick Jackson, director of community engagement for the Washtenaw Sheriff's Office.

Jackson is part of the team looking into the case.

Using public bus video, his team was able to discover that Adriana Davidson did come to school Friday morning, but she left soon after. Friends said she wasn't feeling well.

The video then shows she came back to school again around noon. She never went inside, and that's the last time she was seen.

One of Adriana Davidson's best friends did share a text message screenshot with her brother, Lopez.

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The best friend allegedly saw her leaving school and texted her "you straight?" and then she responded "no."

This is the last anyone's heard from Davidson.

Her cell phone was allegedly found that afternoon on the high school tennis courts by a student, who gave the phone to Davidson's best friend.

The phone is now in police custody.

Davidson's father suspects foul play.

"When I found out that Addy was potentially missing, I knew right away she didn't run away. The red flag for me was the phone," Lopez said.

"What teenage girl just wanders off and leaves her phone and doesn't contact someone?" Jackson said.

According to police, Davidson was last seen Friday afternoon at noon wearing a green coat, black UGG boots and clear framed glasses.

Family spent all of Sunday handing out missing person flyers of the 15-year-old.

"I know that wherever she's at she's not there willingly," Lopez said.