Eye color is more complex than that. Blue-eyed parents occasionally do have brown-eyed children. Also, there's a separate gene for central brown color, and eye color can change as you age too.
My dad had light blue eyes and my mom brown. My syster has my dad's eye color, and I was born with brown. They turned hazel when I was about 45.
My mother always lamented that she would most likely be genetically 'doomed' to having only blue eyed children. She comes from a family of dark complected, dark or black haired, and dark brown or brown/green eyed people. My dad parents were one blue eyed, the other deep brown. She stood out, uncomfortably so to her, because of her very blue eyes and contrasting very dark hair. With a blue eyed husband, she knew brown eyes would be unlikely. Two siblings have blue eyes, mine are a deep green and my other sister's are deep gray with gold flecks. In addition, mine were just as blue as my blue eyed siblings when I was born but 'turned' into green by the time I was in the 5th grade, as photos show. I am the only one 'dark' one, too.