It's been said that everyone has a doppelgänger, but some don't meet them until later in life, like these celebrities. As stars like Brad Pitt, Cameron Diaz, and Leonardo DiCaprio age, they start to look like older actors like Robert Redford, Ellen Barkin, and Jack Nicolson. We bet you probably didn't even notice!

MUST SEE: Christina Hendricks, Lucille Ball, and More Iconic Redheads Who Surprisingly Don't Have Naturally Red Hair

Click through the gallery to see celebs who are slowly transforming into other stars.