Kevin Ryan was a commercial transport passenger in the 24th century.
In 2328, the SS Kogin ferried him and his traveling companion Paulina Ryan from Dallas, Texas, Earth to Holberg 917G. His manifest was accessed by Lieutenant Commander Data aboard the USS Enterprise-D in 2370 by reviewing this data in the commercial transport database. (TNG: "Inheritance", okudagram)
This character was only mentioned in writing.