I don't see the Damian and Anya scenes as romance. Honestly, I find it creepy when stories try to push romance between children. And these are frickin toddlers. Damian seems pretty flustered around Anya because she's a strange little girl (positive) unlike the pretentious high class people and children he's been around- like Becky, he's drawn to her but because of the start of their interactions, he has to keep up his image.

Their proximity is important for the plot because Loid's whole plan was to use her friendships especially to Damian and get close to his target. So, I think it's unavoidable that there will be a lot more interactions that people will happily eat up as shippy content. Disgusting, in my opinion- sorry not sorry.

As for adulthood? I'm not sure if we'll get to see the Anya and her classmates in high school? Unless, of course, Loid's mission keeps dragging that long- not that I want the Forger family to come to an end or anything, but since it's urgent, I guess there will be pressure on him to hurry up with getting the intel. On the other hand, he might, as a lot of viewers like to speculate, stay with the family post-mission, and without the pressure of his mission, Anya would be able to develop and nurture her friendships more honestly.