I received my 6 month old son's passport, but am not sure how to validate with a signature.

I've heard that a parent needs to sign the child's name, but am unable to find that written on an authoritative site. The link below states how to obtain the passport, but not how to validate it for an infant:

http://travel.state.gov/passport/get...inors_834.html

Where can I confirm the policy?

Thanks.

You were looking in the wrong section, your answer is in FAQ #14

http://travel.state.gov/passport/fri...1741.html#ca63

In the space provided for the signature, the mother or father must print the child's name and sign their own name. Then, in parenthesis by the parent's name, write the word (mother) or (father) so we know who signed for the child.