A 76-year-old Bill Gothard reportedly told teenager Emily Anderson that he loved her, put a hand on her thigh, then took her by the hand and escorted her up to his office. All the while, a man was there, working on his computer and witnessing Gothard’s grooming for abuse, Anderson says.

For the first time, Anderson, an alleged victim of Gothard’s sexual abuse, is publicly naming the male witness she described in the hit Amazon docuseries “Happy Shiny People.” The witness is David Waller, brother-in-law to disgraced reality TV star Josh Duggar, Anderson wrote yesterday on her Thriving Forward Facebook page. Waller’s wife, Priscilla Waller, is the sister of Josh Duggar’s wife, Anna Duggar.

Waller also is a pastor at Fairpark Baptist Church, an Independent Baptist Church in Fort Worth, Texas.

Anderson hadn’t released Waller’s name for the documentary, which was the “biggest…