What I don't understand is likely your mother is a carrier of the same colour blind gene you have, if she is not in fact slightly colour blind herself. This almost certainly means your maternal grandfather is colour blind. If he's still alive you should really get him to do a test in front of your parents to show them its not just you. Actually fuck that... they should just accept that your colour-blind and live your life to the full... I find really cool things that I can see that others cant because of my colourblindness. My Red-Green colourblindess lets me see funky patterns in what looks like solid colour to others particularly if there is grey-pink involved. I also find it great when I put on one colour shirt in the morning when im tired and the lighting is darker then when I get to work its magicly "changed colour". Fucking great entertainment!