Um, not really that odd.
I am mixed race, african/german with a white partner. We both have dark brown eyes, he is.... white.
White. and i mean white with freckles and blue eyes. my mother is white with blue eyes, i must have a blue eyed recessive gene, as must my partner, for our child to have blue eyes.
Coloured. - very dark skin, clearly got a fro, and has the telltale blue bum of an african child. Dark eyes to the point of blackness, and the solid chalk white teeth of an african.
They are different sexes, if twins, would have been the same as the example given.
I do remember another such "rare" example, where it turned out the different eggs, had been fertilised by different men.... its possible...