Instructions
Make your piñatas happy before attempting to engage them romantically. Giving them names, feeding them candy, throwing parties for them and keeping a healthy garden ensures that they will be in good spirits and interact positively.
Hover your cursor over one piñata and press "A," then move your cursor to another piñata of the same species and press "A" again. This engages them.
Complete the mini-game that ensues, involving moving a piñata through a maze with a time limit to the newborn piñata at the end.
Press "A" when you reach the newborn. The mini-game will disappear and your piñatas will go to the nearest house to bring a new piñata into the garden.