As mentors, women and men are equally expected to advance their mentees' careers. However, in many contexts, women are still undervalued compared to men. This gender bias also applies to women mentors and may influence the evaluation of their mentees' independent work, i.e., work produced without their mentor. We explore two theoretical predictions regarding a relative evaluation discount for independent work produced by mentees of women versus men: the Matthew Effect and status characteristics theory, which differ significantly in their implications. Analyzing citations accruing to publications of comparable quality by scientists with prestigious early-career mentorship, we find a 13% citation discount for mentees of women compared to mentees of men. This discount extends from collaborative work to mentees’ independent work, regardless of the mentee's gender. Differences in the extent of this citation discount across groups of evaluators align with status characteristics theory rather than the Matthew Effect. The findings expose a consequential role of gender in mentoring the next generation with implications for research on mentorship, gendered evaluations and spillover effects, as well as transgenerational biases in cumulative knowledge building.