וַתַּ֣הַר ע֔וֹד וַתֵּ֕לֶד בִּלְהָ֖ה שִׁפְחַ֣ת רָחֵ֑ל בֵּ֥ן שֵׁנִ֖י לְיַעֲקֹֽב׃
Bilha, l’esclave de Rachel, conçut de nouveau et enfanta un second fils à Jacob.
Haamek Davar on Genesis
Rochel’s handmaid. This is reiterated here to indicate that unlike Hagar, she continued to treat her mistress with respect even after she conceived.