Olympic gold medalist Mary Lou Retton celebrated a milestone in her daughter’s life weeks after facing backlash over receiving financial donations to cover medical bills. The retired athlete announced her second-oldest child, McKenna, picked out a wedding gown ahead of her nuptials. “She said yes to the dress,” Mary Lou captioned her latest Instagram post. McKenna, who followed her mom’s footsteps while attending Louisiana State University, got engaged to boyfriend, Braden Doughty, just last month. While many of Mary Lou’s followers congratulated McKenna, it was noted in the comments that she …