Aaaah sorry for the late reply, was on vacation!
ALSO THIS, he's a grown up Len I know it in my heart.
It doest sadly, I was trying to hatch an egg yesterday when returning to home and it was like, 4,80km of 5km, and it didnt hatch.
Also you live in america?? Tauros are exclusive from there I think, you're very lucky tho! The exclusive pokemon in europe is mr.mime and I havent seen any :/