Pete Taylor has said that he was "hurt" when Katie dropped him as a coach after his split from her mother.
With Pete in her corner, Katie won numerous world titles as well as a Gold Medal in the Olympics in London.
Katie has since turned pro and now has two belts to her name but Pete is no longer involved in her career.
Speaking on Paddy Holohan’s No Shame podcast, he said that he wasn't sure if Katie would have been as successful if he was still in her corner.
"I don’t think she’d have gone pro if I’d have been still there. She wouldn’t have gone pro.
"I don’t know if she’d have won another gold medal in Rio if I was there.
"The last major title she won was when I was there. Then I don’t know if she’d have gone on, even if I was there, if she’d have won another Olympics in Rio.
"She has good morals. She said if you’ve split up with my mother then I don’t want you in my corner.
"She knew what the outcome would be. She knew that she’d be missing me in the corner but she still had the morals to go ahead and do that.
"You’ve got to respect that. She was reared good.
"There’s not many people who’d risk losing a European, Worlds and Olympic title by not having your father as a coach.
"She backed her ma. You risk your career, which she did do, but she still did it. But you’ve got to admire that as well — although it’s hurtful for me — but I’ve still got to take my hat off to her."
He concluded by saying that they still talk but do not talk about boxing.