• Jennifer Aniston turned 51 years old on February 11th, with plenty of celebrity pals, including Reese Witherspoon, wishing the actress a happy birthday.
• "Friends" costar Courtney Cox wished Aniston a happy birthday on Instagram, posting a photo of the two looking eerily similar.
• In the photo, Cox donned a wig and a pair of glasses to match Aniston's look.
• But Cox, in the caption, wrote: "No matter how hard you might try... there's only one Jennifer Aniston."
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