It's available on the sport court if you reach 20 strength points ^^
I think I had already done it like four or five months ago? Basically the same dad asked this question I figured out how to do it and it was pretty amazing. I hate getting the mom to full horn in is only just to give her a back rub, I wish we could do more with her same with the neighbor girl, I'm already loving the new update though I want to catch all the girls in their routines!