Yellow labrador retriever litters?

Question

I have a yellow labrador retreiver who has been bred twice now with 2 different chocolate male labrador retrievers. Each litter has had ALL black puppies and the background of the mother is almost all yellow and the fathers are mostly chocolate with few black and a good amount of yellow. Anyone know why?

Answer 1

GET YOUR FRICKEN DOG SPAYED IF YOU DIDN'T LIKE THE COLORS THE FIRST TIME THEN WHY DID YOU BREED HER THE SECOND TIME

Answer 2

Any 3 of the possible standard coat colors is possible with labs, regardless of the parents colors.

This explains it more.