Hugh Jackman Wishes Ryan Reynolds' Mom Happy Birthday with Cheeky Jab at “Deadpool ”Costar: 'Stand-in Son'

"Blasphemer!" Reynolds quipped in a comment on his friend's Dec. 3 Instagram post

Hugh Jackman is honoring Tammy Reynolds as she celebrates another trip around the sun!

On Tuesday, Dec. 3, the actor, 56, posted a tribute to Tammy — who is the mother of his close friend and Deadpool & Wolverine costar Ryan Reynolds — on Instagram, alongside a carousel of photos of himself with the birthday gal and one with Ryan, 48.

"Happy Birthday to the one and only, Tam Tam!" Jackman began his caption, using the rest to poke a bit of fun at his friend by leading with Ryan's three older brothers' names first.

"Patrick, Terry, Jeff and I love you so much. And of course, your emergency, stand-in son, Ray. Rolf…? Ryan?" the Greatest Showman actor quipped.

"Blasphemer!" Ryan wrote in a comment on Jackman's post.

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Ryan posted his own Instagram tribute to his mom as she celebrated her milestone birthday on Monday, writing, "Tam Tam is 80!!! Wishing my mom the happiest birthday."

In his post, the Spirited actor shared a video montage of funny moments between himself and Tammy, joking in the caption, “I still remember the first time I saw her. I was sitting in the backyard one night, holding a flashlight and dozing off. Suddenly, she just came waddling out of the shed. It scared the s--- out of me!"

"Later, I rode my bike, racing away from our dry desert home and into a deciduous rainforest which somehow coexists just a few blocks away," Ryan continued. "Eventually Mom was all like, ‘f--- it,’ and we straight up, flew into the air while she whispered, ‘Elliot’ every few seconds in a low groan that was both off-putting and quite off-putting."

Continuing with the plot of 1982's E.T. the Extra-Terrestrial, he wrote, “Later she waddled back into her spacecraft and left earth forever, even though I saw her like four times today alone."

"Happy Birthday mom. You are the best mom," Ryan added on a more serious note. "We love you. Your grandbabies love you. Most importantly, @thehughjackman loves you.”

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Related: Ryan Reynolds' Parents: All About Mom Tammy and Dad James Chester Reynolds

As Ryan marked his 48th birthday in October, Jackman shared a series of photos with his longtime friend to Instagram and joked in the caption, in part, "On this day we celebrate Tammy … for delivering Ryan. 🎂 🎉 🎈."

The Free Guy actor's Oct. 23 birthday came just 11 days after Jackman himself celebrated his 56th birthday on Oct. 12.

The pair marked their shared birthday month in a photo that Deadpool & Wolverine director Shawn Levy posted to Instagram Oct. 7, in which Ryan and Jackman held a large cake adorned with flowers.

"October is the best month for buddy birthdays🎂," Levy, 56, wrote in a caption to his photo at that time. "A perfect fall day celebrating early with two of the BEST❤️💛."