Nina Caliente

Nina Caliente is a pre-existing, playable sim that comes with the The Sims 2 game. She lives in a small condo with her twin sister, Dina Caliente in Pleasantview.

Both Nina and her sister, Dina, are romantically involved with town womanizer Don Lothario; apparently each without the other's knowledge. Nina starts the game with long red hair and wears a black halter top with pink cargo pants.

Nina and Dina are the daughters of Flamenco Caliente and Nighat Caliente (née Al Mahmoud), now deceased, both also of Pleasantview. The sisters are, also, part alien from their paternal side: their grandfather, Nestor Caliente, gave birth to their father, Flamenco Caliente after being abducted and impregnanted by Pollination Technician.

Player stories
I don't know about anyone else, but it seems that this sims father is an alien/human hybrid. Her grandfather is apprently an alien.