Fraternal

[Sarah]

Twins that do not look alike.
Most people think of identical twins when you say twins, but twins are just people that are born on the same day (as you should know if you are over 6).
Because of that, fraternal twins do look a little like, but not enough to be considered twins. Often it is assumed that they are siblings of different ages or cousins.

[Tina]

Of or like a brother or brothers.