Blue eyes aren't found much in dogs, but those born with the merle pattern have a better chance. This is because the variant that created the stunning merle colors, MITF, also makes the blue eyes.

Related: Adorable Merle Cocker Spaniel Puppy Has Rare Eye Color Only Seen In 5% of Dogs Right along with that marbled fur, it's impossible to ignore Effie's magnificent, bright blue eyes.

With merle being so dominant, a lucky pup only needs one copy to come out merle — Effie is proof! Related: Adorable Merle Cocker Spaniel Puppy Has Rare Eye Color Only Seen In 5% of Dogs ...