How Do I Mate My Tamas?

[Fida]

I want to mate my V2 and V3. They are both the right age to mate (one is 4 and the other is 5). However, I can't remember how to mate them! Can someone help?

EDIT: Yes they are "partners" in friendship level. The little heart even shows when they visit each other. However they will. Not. Mate!!

 

[iceringer]

on the heart icon select "others" on both versions and press B on one version

 

[Fida]

There is no "Others" on V2, there's "Version 1", but that's beside the point.

All that happens is that one gives the other a present. What's going on?