Nadab, Eleazar, and ELI were all sons of Aaron, the first high priest of the Israelites. Nadab was the eldest son of Aaron and his wife Elisheba, and he was appointed as the second high priest after his father. Eleazar was the second son of Aaron and Elisheba, and he succeeded his father as the third high priest of the Israelites. ELI was the youngest son of Aaron and Elisheba, and he was a priest in the Tabernacle.