Oh yes, before I forget, this can apply to secondary characters, a possible Emellie Pregnancy can be a super special event that requires other events to be unlocked...
(...because, I'm more interested in seeing Victoria and Bronwen Pregnant and Lactating than Emellie necessarily...)
(...but also nothing against a special event in which the MC stimulates Emellie to Lactate without knock her up as it happened with Victoria, even more so because Emellie is super curious about these things XD)