וַתַּ֣הַר ע֔וֹד וַתֵּ֕לֶד בִּלְהָ֖ה שִׁפְחַ֣ת רָחֵ֑ל בֵּ֥ן שֵׁנִ֖י לְיַעֲקֹֽב׃
E Bila, serva de Raquel, concebeu outra vez e deu à luz um segundo filho a Jacó.
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.