To mock a mockingbird and other puzzles

Normal Birds

Lets use the term /normal/ for a bird that is fond of at least one bird. Q7 (https://www.facebook.com/groups/mockamockingbird/permalink/168283056892135/) asked you to prove that every normal bird is happy (the reverse is not necessarily true).
Prove that if composition C1 holds, and if there is at least one happy bird in the forest then there is at least one normal bird.