The sister of Tahpenes is not named in scripture but she was a sister-in-law to the Pharaoh of Egypt during the time of King Solomon, about 3,000 years ago.
The Pharaoh gave her in married to a man named Hadad, who was an Edomite of royal blood and an adversary of King Solomon. The sister of Tahpenes gave birth to a son with Hadad named Genubath. The son Genubath was raised by his aunt Tahpenes in the royal palace.
Because Genubath was raised by his aunt Tahpenes, some scholars think that it's possible that the sister of Tahpenes had died, perhaps during the childbirth of Genubath.
The sister of Tahpenes is mentioned twice in scripture, in 1 Kings 11:19 and 1 Kings 11:20.
Next person in the Bible: Tamar, daughter-in-law of Judah