K'Ehleyr, the daughter of a Human mother and a Klingon father, was a special emissary of the Federation in the 2360s.
In 2365, she came aboard the USS Enterprise-D on an urgent mission to intercept the Klingon sleeper ship IKS T'Ong, which was about to become active. The vessel would have been unaware of the Federation-Klingon alliance, therefore posing a threat to Federation establishments in the Boradis system. While searching for the T'Ong, she renewed her relationship with Worf, but refused to marry him when he asked her. Due to this short renewal, however, she gave birth to a son (Alexander Rozhenko) a year later.