Data on two offspring performance traits (seeds per capsule and flower number) in greenhouse studies of Collinsia heterophylla to investigate indirect benefits of mate choice. We performed two-donor pollinations during successive floral stages and with different competitor types (outcross and self) to assess how stigma receptivity and two pollen traits known to affect siring success influence offspring performance. We also investigated the link between seed production in mothers and offspring as an indication of heritability of this trait, and differential resource allocation by studying the influence of sibling performance in the same capsule.