Twins in my current household, Hannah (Reddish blonde hair) and Hayden (black hair)! I also have another child in the household named Harrison, but he's away at boarding school so I won't see him again until he's a teen
http://i1381.photobucket.com/albums/ah222/alexstone010/Screenshot-942_zps6zbkbss7.jpg
http://i1381.photobucket.com/albums/ah222/alexstone010/Screenshot-940_zpsimio7q74.jpg
http://i1381.photobucket.com/albums/ah222/alexstone010/Screenshot-944_zpsiah9qqbo.jpg
Was not expecting twins. My sim was pregnant and was expecting a girl, so I decorated the nursery with one crib, got one high chair, one stroller, already had the name chosen etc and then...twins!