I am the oldest brother in the family and the second oldest of 5. Noone else in my family is gay... (or admits to it... )

I once knew a family in South Carolina where there were 4 boys. All were gay. I know a family from Vancouver of two brothers, both are gay. I know a family in Thailand with 2 boys, both are gay, AND the sister is a lesbian!

I don't think the survey results are indicative of any realistic trend based upon how many siblings or older or younger, I think it is much more genetic than just your position in the ladder of the family.