Family bin

The Family bin is where a Sim or a family is stored until they have a Residential lot to be placed in. It's as if the sims are "in limbo" when they're not living on a residential lot. When you create a family in Create-A-Sim mode they go straight into the family bin, and from there you can move them into a lot.

Telling a Sim to "Find Own Place" also places them in the family bin.

Until University, Sims or Sim Families in the Family bin could not be combined in other households. This feature is intended to be used with Teens who have gone to College and graduated to then join the family again!

The family bin, unlike the lots and houses bin, is neighborhood specific, so you can't move families from one neighborhood to another. Sub-neighborhoods are the exception, though. A sub-hood (with the exception of a university) attached to a neighborhood shares it's family bin. So, for example, if you attached a Downtown to Pleasantview, any of Pleasantview's inhabitants could go to live in Downtown and vice-versa.