Plato on Family (Help me Lazyweb!)

[lightcastle]

One of the stories/episodes for the play we're possibly putting together for the Fringe involves family and something resembling the whole idea that people shouldn't raise their own children. I know Plato goes into this some in the Republic (which is what I am riffing off of here). Does anyone know if there's a decent quote connected to it?

For instance, "Who Guards the Guardians?", associated with the problem of the Guardians and the Noble Lie.

Is there one associated with the corruption possible with raising your own children?