Come on pitts, you can't possibly believe cops have "little or no contact" with families after the initial interview. An ongoing investigation means just that. How the heck does LE know they got everything they wanted in one interview when the case is fresh. There are always questions cropping up, events that need clarified, facts that need to be checked and rechecked.
There was an arson case at my neighbors house and the cops questioned the family and neighbors four times over a two month period.
The Elizabeth Smart case was unique in itself. I don't think you can compare it to this case. And, I doubt we know how many times the cops actually questioned the Smart family. As for Ron's attorney's opinion that witness statements are limited in value after given, that's what I'd expect a defense lawyer to say.
My point is that I believe if a parent wanted to find their child they would be talking with the cops constantly. And, I've never seen a sign at the cop shop forbidding crime victims from being there. JMO