My little family should have 5 kids, but if you pull up details while it says 5 kids, there are only 4.

Anyone encounter this -- missing family members?
Why does/did this happen and how do I find the missing member?

How old are the children? The older ones go off to college sometime after they turn 18. They are removed from the details screen at that time, since they can no longer be selected in the game, but you can see them on the Family screen and click their picture to see some of their details, as well as make notes about them.

Och! Yes you are right, that's exactly it. One of the little guys turned 18 and isn't in the house anymore.

Thank you!