Dear Ms. Kay,
Thank you for posting your request on History Hub!
The actual passports that are issued to individuals that would have the stamps on it indicating foreign travel are not retained by the federal government. They typically are not collected by the federal government during or after a person’s life unless the passport is revoked or surrendered for various reasons.
The State Department has custody of passport applications dated after 1925. For information on how to request an application, please visit their web site at https://travel.state.gov/content/travel/en/passports/have-passport/passport-records.html. All requests for passport records issued after 1925 to the present should be mailed to the U.S. Department of State, Office of Law Enforcement Liaison, FOIA Officer, 44132 Mercure Circle, P.O. Box 1227, Sterling, VA 20166.
We hope this information is helpful. Best of luck with your family research!