'The Bachelorette's' Sister Chrystie Corns Takes Back Criticisms of J.P. Rosenbaum

"I made a big mistake," she said in a new interview in response to her negative remarks about her sister Ashley Hebert's fiance.

Viewers saw Ashley Hebert get engaged to J.P. Rosenbaum on the season finale of The Bachelorette earlier this week, but Hebert's sister Chrystie Corns has made it public knowledge that she wasn't behind her sister's

"I made a big mistake," Corns told People of her negative remarks about Rosenbaum. "As I started watching the season, however, it's very clear to me that J.P. was the one. He was the best choice."

Nearly 24 hours after the finale aired, Corns reversed her opinion of Rosenbaum, taking to Twitter to say her peace. "My heart was in the right place..my mouth was not," read one of the tweets that she wrote. "I feel truly horrible about my behavior," read another one. "She [Ashley] has consistently made the right decisions for her life, I feel foolish for doubting her," read another tweet that Corns wrote.

But, as viewers can remember, Corns was critical of Rosenbaum when she first met Rosenbaum, noting that she didn't see the love connection between the two.

"What I didn't take into consideration at that point was that she had been on this eight-week journey and she was really tired," Corns said.

Now, Corns refers to Rosenbaum as Hebert's "knight in shining armor" and says she and her sister are best friends.

But Rosenbaum is milking it for all its worth. "I want to make it up to him but he won't let me forget it," Corns, who appeared on TLC's Extreme Couponing, said. "J.P. says if he has anything to do with it I'm going to have to fight for the right to be maid of honor."