According to the book, son Oswald Freeland was born in Canada after the family arrived there in 1821.
The only document I have found that mentions him by name is an 1851 U.S. Passport application (referenced in the family history). This is the oldest passport application I have in my family database.
NARA Series: Passport Applications, 1795-1905; Roll #37: 23 may 1851-30 Sep 1851. Record for Oswald S. Freeland, 1851.