I was just curious so I could give my female runner a break from having children.. Ha. Is there any correlation between a runner and his/her children becoming runners? If so, what is the likelihood of this happening?

Also, in general, as early as the age of 2, are you able to tell if you have a runner by seeing "running" in the villager's "likes" on the detail screen? Or, does this "like" appear as the villager gets older; if the latter is true, at what age would this appear?

Thanks!