They don't know that we know they know we know...how epic this Friends reunion is!
"How lucky am I to celebrate my birthday with these two??? I love you girls. So much ♥️," Cox, who played Monica on the hit show, wrote on Instagram alongside a photo of the three.
"LOVE you girls! Happy happy Court," commented Kudrow, who played Phoebe.
Kudrow, 55, also wrote on her own page, "Just remembering Court, I will ALWAYS be older than you. HAPPY BIRTHDAY lovely Courteney!!"
"Only wiser my sweet," Cox replied. "Never older. I love you."
Aniston, who is 50 and who played Rachel, is not on Instagram.