Click the link below for Passport Forms to apply for a Passport
https://travel.state.gov/content/travel/en/passports/apply-renew-passport/under-16.html
The most common form is:
DS-3053 – Passport Form, “Statement of Consent: Issuance of a U.S. Passport to a Minor Under Age 16”
Passport Form DS-5525 is a Statement of Exigent/Special Family Circumstances for Issuance of a U.S. Passport to a Minor Under Age 16
Most people can use form DS-5525, if you have had difficulty getting the non-applying parent to give consent for your minor child under 16 years old to obtain a passport book or card.
Attach a statement detailing the reason why the other parent can’t/won’t sign the consent form (DS-3053).
Attach any evidence regarding your circumstances.
Explain methods you have used to try to obtain consent.