Within tonight's sermon passage was the sometimes troubling Titus 1:6:
An elder must be blameless, the husband of but one wife, a man whose children believe and are not open to the charge of being wild and disobedient. Titus 1:6 (NIV)
Gerard mentioned the Nine Marks website has some helpful comments on this verse. (There's plenty of other interesting articles on this site.)
More links
Here are some more specific links:
Unbelief in an Elder's Children -- Exegesis
Unbelief in an Elder's Children -- Practice
At what point does a child’s misbehavior disqualify his father from being an elder or pastor?