Serah is a female and is counted as one of the sixteen descendants of Zilpah. Heber and Malchi-el are Zilpah’s grandsons.

Quoted with permission from Reyburn, William D. and Fry, Euan McG. A Handbook on Genesis. (UBS Helps for Translators). New York: UBS, 1997. For this and other handbooks for translators see here .