Both parents DO NOT need to be present. The rules have recently been tightened up, but one parent and the child, with the proper documentation, can still appear before the passport agent without the other parent. The below was copied 10 minutes ago from the Department of State's passport web site. The major change is that the document that substantiates the non-appearing parent's permission must be notarized.
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Present Parental Application Permission Documentation
(for minors under age 14)
1. Both parents must appear together and sign or
2. One parent appears, signs, and submits second parent's notarized Form DS-3053, Statement of Consent: Issuance of a Passport to a Minor Under Age 14 , authorizing passport issuance for the child or submits a notarized , written statement of consent from the non-appearing parent (including the child's name and date of birth, as well as parent's identification information or a copy of his/her ID) authorizing passport issuance for the child