Here's an interesting site which gives the meanings of Ulfang and sons names:
Uldor '*hideous-lord' (LR:396)
Ulfang '*hideous-beard' (LR:387,395)
Ulfast '*hideous-tangle-hair' (LR:381,396)
Ulwarth '*hideous-betrayer' (LR:396,397)
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In HoM-E V,
The Lost Road and Other Writings, in "The Genealogies", here's what it says about Dad and sons:
Ulfand the Swart (Ulfang the Black) - b. 100 (400 FA)
Uldor (later called the Accursed) - b. 125 (425 FA)
Ulfast - b. 128 (428 FA)
Ulwar - b. 130 (430 FA)
The first dates are the original dates given by Tolkien.
In later Tolkien chronology, the dates would have been adjusted up by 300 years. (Adjusted dates in parentheses)
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