I have 3 kids and 2 of them have blue eyes 1 brown eyes, thier father and i both have brown eyes and he is thier father. My mother has blue eyes so do his brothers, so eye color doesnt matter. Eye color dosent mean that the kid is not yours. Hope this helps!
Do you suspect that your wife has cheated, has she cheated in the past that you know about? If their is no reason to think that ur wife has cheated, then dont think it, it can ruin a relationship fast!