Background
Despite the fact that Donna is half Jamaican and Vince is Caucasian, they would have expected to welcome mixed skin tone babies, not one white and one black daughter. But hey, life never quite works out as we expect it to.

Background
Non-Identical Twins
First, Lucy and Maria are non-identical twins who were born from separate eggs, therefore they did not inherit all of the same genes. Additionally, their mom comes from a mixed Jamaican heritage, which is where she got her Afro-Caribbean and white skin. But no one ever anticipated that Lucy and Maria would be so different.

Non Identical Twins