When it comes to birthdays, you can count on Reese Witherspoon!

The Big Little Lies star is the queen of marveling over her gal pals on their special days, never forgetting to honor them with a special post over social media.

WATCH: Ava Phillippe Wishes Sweet Happy Birthday to 'Best Friend' Mom Reese Witherspoon

She most recently celebrated the birthday of fellow actress Kate Hudson, taking to Instagram to pen a sweet message to her dear friend, who turned 38 on Wednesday.

"Happy Birthday @katehudson!!" Witherspoon, 41, captioned it. "Keeping shining bright with your gorgeous spirit! ?✨?"

One day earlier, the actress couldn't help herself from gushing over Jennifer Garner. The brunette beauty turned 45 on Monday, and what would a birthday be without a post from Witherspoon?

"Here's lookin' at you, Jen!" the message read. "Happy Birthday to my gorgeous friend #JenniferGarner who always laughs at my jokes and my bad dance moves! Love you!"

Hear more on how Garner celebrated her special day in the video below!

WATCH: Reese Witherspoon Sends Birthday Wishes to Jennifer Garner