The Stardust actress, 62, took to social media to wish her younger sister, Dedee Pfeiffer, 56, congratulations on a new acting gig.
Michelle shared a photo of "my sis" in a promotional snapshot for ABC's Big Sky and was thrilled to call the project; "The best broadcast show of 2020."
WATCH: Michelle Pfeiffer showcases her impressive Catwoman whip skills
The Hollywood star has plenty to be proud of when it comes to the new drama, since her husband, David E. Kelley, produced it too.
Dedee didn't plan to follow in her famous sibling's acting footsteps, but it happened more by accident.
"I became an actor through trial and error," she said in an interview on Medium. "Long story short, by the time I was 18 years old, I had been working numerous jobs since I was ten.
Michelle shared the photo of Dedee on set
"My sis was working on Scarface and I told her I wanted to 'try' acting because everything else bores the [expletive[ out of me!"
While she hasn’t reached the dizzy heights of fame that Michelle has Dedee, has nearly 70 on-screen credits.
Amusingly, Michelle previously revealed she wanted to set her sister up with her husband because she thought they were better suited.
Speaking about the group date at a bowling alley, Michelle - who has another sister, Lori - told Candis magazine: "He [David] talked to my sister and I talked to his friend, and he and my sister seemed to be hitting it off, so I thought maybe we should set them up instead, but the friend who was setting us up said, 'Don’t you dare.'"
Her friend was right! Michelle and David have been happily married for 27 years and share two children together.
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