In March 2018, 16-year-old Amy Yu went missing. Nearly two weeks later, she was located at a resort in Mexico with her best friend’s 45-year-old father, Kevin Esterly. Amy had grown close with the family over the last eight years, and Kevin and his wife, Stacey, considered her as a “fifth daughter.”

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Did Kevin and Amy’s relationship cross the line? Stacey says she has no proof that the two had a sexual relationship, and they both deny it, but she does claim she saw an “inappropriate” conversation between the two on Facebook.

In the video above, a passenger who was on an airline with Kevin and Amy describes the interaction he claims he saw between the two. How does Stacey respond?

WATCH: 'In My Heart, I Don't Want To Believe That They Were Sexual,' Says Woman Whose Husband Ran Away With Daughter’s 16-Year-Old Best Friend

During an exclusive interview airing on Dr. Phil on Thursday, Stacey accuses her husband of almost 14 years of more lies and betrayal. And hear what happened when she spoke to her husband for the first time after he was arrested, and what she wants to say to him now. Check here to see where you can watch.

TELL DR. PHIL YOUR STORY: Inappropriate Relationship?

What Woman Wants To Ask Husband Who Ran Away With Daughter’s 16-Year-Old Best Friend