How do you adopt a unicorn without cheats

you have to become friends with the unicorn and then you ask it if it would like to live with you, it will say no to you and the unicorn should say "i will consider your offer if your kind to all animals" or something like that. then you go back to your house and adopt two stray animals that come to your door (this might take a while to do). once you have adopted two strays you go back to the unicorn and ask the same question again it will say yes to it this time.

if you cant be stuffed to do this here is a cheat way...
when you see a unicorn you hold shift on it and click the one that says "add to active family" and it will be in your family (this works with dogs and cats too)
(WARNING: if your lifetime wish is :fairytale finder the cheat way will not finish it!)