He confided in me about wanting to bring his daughter to the petting zoo. He's mad because of something his daughter said: calling the OW's husband... Daddy. It hurt him. Now, he's really intent on getting "his own" time with her. He hates the parasite's husband more than I hate the parasite. Irony.
And why shouldn't she call him daddy? She's living with him, her siblings all call him daddy - he IS her daddy at the moment. Your H was just the sperm donor.
