Abihu in the Bible Encyclopedia - ISBE

a-bi'-hu ('abhihu', "father he is," or "my father he is"): Second son of Aaron, the high priest (Ex 6:23). With his older brother Nadab he "died before Yahweh," when the two "offered strange fire" (Lev 10:1,2). It may be inferred from the emphatic prohibition of wine or strong drink, laid upon the priests immediately after this tragedy, that the two brothers were going to their priestly functions in an intoxicated condition (Lev 10:8-11). Their death is mentioned three times in subsequent records (Nu 3:4; 26:61; 1 Ch 24:2).

Link: https://bible-history.com/isbe/A/ABIHU/