My little brother turned to be gay and my parents dont accept?

i seem to be the only one who understands him. well we are devout catholics so of course my parents dont believe what he i saying. but he keeps telling me why is it wrong? and he didnt ask to be this way. when he tells them that my parents say "the gay people are already brain washing you saying that your born that way" . well im not being stereotypical or anything but i always had a feeling my brother was gay but my parents dont buy it. put it this way could you ever turn a straight guy with a wife and kids gay? no right? so how do they expect my brother to change. does anyone agree with me because im like his only support