"I was against it at first," Tom said, "honestly didn't go to a few things because I was pretty much against it."
But as Brooke-Lynn continued to wrestle, it didn't take long before her dad and Uncle Paul -- who also coaches her -- became her biggest supporters.
"Once I started seeing her wrestle, I saw the potential and it just kept growing and growing and growing," Paul Rush said.
"You watch her go into these matches and you just wonder how she's going to do it, and she does it," Tom said.
Brooke-Lynn began her wrestling career at the age of four, and won the second match she participated in. Since that first victory, she's had one thing on her mind each time she takes the mat.
The 12-year-old is a four-time state champ in Missouri and Kansas, and a two-time winner in Iowa --all of which came in the girls division.
But the highlight of her career came at the Missouri Youth Wrestling Championships in 2014.
"A couple weeks ago at state when I beat Cole Gripka and went to the medal rounds," Brooke-Lynn said, "it was my first time ever to medal at boys state. It was pretty awesome."
She began wrestling for St. Joe Metro before switching over to War Machine Wrestling. Brooke-Lynn's always looked up to Benton High School's career wins leader Tyler McNutt since her first experience with the sport.
"I want to be like him."
The seventh grader at Bode Middle School is setting lofty goals just like McNutt. Rush hopes to eventually achieve state champion status at Central High School, then continue wrestling collegiately at Missouri Valley.
"She's going to go very far," Paul said. "She's got goals, and she's going to achieve those goals."
"She's all heart. Even if she's not strong enough, maybe she's not technical enough, but if you watch her wrestle, she's determined," Tom said. "She's going to win that match one way or another."
Now after watching his daughter put everything she's got into the sport over the last decade, Tom's changed his opinion on girls in wrestling.
"I just didn't think it was a girls sport at first. Now, it's a girls sport. It's definitely a girls sport in my eyes."