Anyway, as far as the question in the OP is concerned, I don't have a problem with two siblings getting married as long as they are consenting adults.
Then you agree that until all mature willing companions are allowed to marry as they choose that the court decision favoring SSM was discriminating and bigoted.
*****SMILE*****
Not sure where you got that moronic conclusion. But being a conservative pin head, your tin-foil hat is probably cutting off circulation to what was once a functioning brain.
The court decided on a case. I agree with the ruling.
In a hypothetical case if it were two siblings, I would hope the court would strike down any laws preventing siblings from getting married.
The same would go for a parent and child if the two were adults and consented to the union.
Why? Because its none of my business what two consenting adults do in the privacy of their own home.