Your bro: "Yo, my sister wants the D"
You: "Nah bro, she's just wants to be annoying"
Bro: "No seriously dude, she wants the D"
You: "Bro, you don't know what you're talking about"
Sister: "Hey You, I want the D"
You: "What is this blackmail?"
At some point you have to realize that your crush is gay and move on.