NET
10 Hosah, one of the descendants of Merari, had sons: The firstborn Shimri (he was not actually the firstborn, but his father gave him that status),
Darby
10 And Hosah, of the sons of Merari, had sons: Shimri the head, for though he was not the firstborn, yet his father made him the head;
KJV
10 Also Hosah, of the children of Merari, had sons; Simri the chief, (for [though] he was not the firstborn, yet his father made him the chief;)