BTVS: TALES OF THE SLAYERS
Kendra parents gave her up for Slayer training at a very early age. Kendra Young did not know her own surname as she studied under her Watcher, Sam Zabuto. She was called when Buffy Summers briefly died at the hands of The Master in 1997.
The uprising of a powerful demon named Kelgor drew Kendra's attention to Sunnydale to help Buffy. The two Slayers joined forces destroy Kelgor and his reign of terror. Kendra was later killed, while trying to protect Buffy's friends from a vampire party, her death activating the next Slayer.