Question 1024512
Any specified result child by child, is 1 in 8. 
There are 2^3 possible results, taking order into account. BGG is one of those results.

1 boy 2 girls, any order, can be

BGG
GBG
GGB

3 different ways of the 8. 

For sake of completion, here are the 3 with 1G 2B

GBB
BGB
BBG

and last, all boy or all girl

BBB
GGG

Now I've listed all 8 possible outcomes.