Logic Puzzles

Why is it not 50% as GB gives the same result as BG?

The fact that one child is a boy has not bearing on the sex of the second child.

Maybe I'm missing something in the way the question is worded?

I thought the same - so looked this up (https://en.wikipedia.org/wiki/Boy_or_Girl_paradox )- there's a section that explains the ambiguity of the question. i.e. did they look for that family with two kids, at least one of which was a boy to ask the question about (in which case pr = 1/3) or or did they choose a random family and then make a statement about the kids in it (in which case pr =1/2).

At least I think that's what it says...