The Stiles family was an extended Human family with a tradition of service in the United Earth and Federation Starfleets throughout the 22nd and 23rd centuries.

Several members of the Stiles clan, including one captain and several junior officers, were killed in service during the Earth-Romulan War. It was also mentioned in reports from members of this family that Romulan vessels were identifiable by a giant bird of prey painted on their hulls.

The memory of that era and of the family's sacrifice was carried by Lieutenant Stiles, who survived his encounter with Romulans, while serving as navigator aboard the USS Enterprise in 2266. (TOS: "Balance of Terror")

This family was only mentioned in dialogue.
An Ensign Stiles serving aboard Enterprise was mentioned in the first draft script of ENT: "Shadows of P'Jem" (written while the episode had the working title "Untitled Andorians Return"), but that character was replaced by Ensign Mayweather for the filmed episode.
According to the novel Starfleet: Year One, "Jake" was the name of one Stiles killed by Romulans. A role-playing games reference book, the Star Trek: The Next Generation Officer's Manual, lists a starship named for another fallen member of the family: the USS Lawrence Stiles. The family tradition of Starfleet service continued into the 24th century in the novel Red Sector, which depicts Lt. Stiles' grandson, Lieutenant Commander Eric J. Stiles.