Not to be a jerk, but I probably wouldn't face it by calling it "some shit like this". It's just a thing that exists. I'd hoped that by the time I was an adult, being gay wouldn't be a thing to be dealt with. It would just be…a thing.
"Hey, Mom. I'm gay."
"Oh, that's cool. Help me get the groceries out of the car."
I'm not naive enough to think that's an absolute possibility, but one can hope. In response to the question, I actually did date a guy whose siblings were also gay. Two gay men and one lesbian-turned-male. She was a very accepting parent, he told me. As for how I'd personally deal with it, that's hard to say. As a gay man, what would it matter to me if all my kids were gay? And I can't speak to the heterosexual parenting experience because I'm not a heterosexual parent. All I can say is that I wish being gay wasn't cause for panic anymore.