A father ignored his hearing loss until his daughter, who took a class on it, pushed him to see a doctor. It was a brain tumor.

Even before she took a class at Auburn University on hearing loss, Rachel Ruhlin knew something was off with her father, Joe. 

"We would say something to him and he would not hear it or he would repeat things and we'd be like, 'Well, we just said that,'" she told CBS News. 

The more she learned, the more she pushed him to get his hearing checked. But he wasn't worried. 

"I thought, maybe back in my 20s I was at a concert that was really loud or something like that and I messed up my one ear," he told CBS News. 

When she was home for Thanksgiving, Ruhlin insisted her father see a doctor. Since his hearing loss was only in his left ear, her dad assumed he'd just be getting a hearing aid. 

"We never would have thought that it was a brain tumor," he said. 

It was a tumor called an acoustic neuroma. If left untreated, it can be fatal. 

"We don't know what would have happened if I didn't take that class," Ruhlin said. 

This Father's Day, Ruhlin and her dad are especially grateful.

"I'm just happy that we'll have many more years together," Joe said.