Allegreno

Tristan's half-brother, named only in the Italian La Tavola Ritonda, though he appears in the Prose Tristan and in Malory's version.

He was born to Tristan's father, Meliadus (Meliodas) and stepmother (named as Agia in the Tavola). Seeking to move Allegreno in place as Meliadus's heir, Agia prepared a poison potion for Tristan. A nurse accidentally served the concoction to young Allegreno, who perished.