Mave Whisperwind is a Priestess of the Moon mentioned in Mojo Stormstout's Strategy Guide, and appears as a random hero in Warcraft III: Reign of Chaos. Night elf surnames are indicative of the family line and often date back millennia. This would indicate that she is from the same family line as Tyrande, although how closely related to Tyrande is unknown. She can be randomly generated in the main campaign and the non-campaign maps.
Mave is not mentioned in either account of the War of the Ancients. Tyrande's rank makes it unlikely that any close relatives who survived would have been unable to find her, so Mave may be a distant relative, if anything.