Ripa posted a montage of photos from Michael's birth, with the disco version of the Star Wars theme playing over it.
"21 years ago today the galaxy was shooketh! Happy birthday HE! We love you BIG," Ripa wrote in the caption.
On Thursday, Ripa posted a photo of Michael as a toddler with his father and grandfather, Saul Consuelos.
"A long time ago, in a galaxy far, far away," Ripa wrote in the caption.
Consuelos also posted a photo of his son all grown up and on a hike, as well as a photo of Michael in a diaper.
"'Go West Young Man.' Happy 21st birthday Michael. Our love for you is only matched by our pride.. xoxo Dad," Consuelos wrote.
Michael was born a year after Consuelos and Ripa, both 47, tied the knot. The couple has been married since 1996 and met on the set of the soap opera All My Children. They celebrated their 22nd wedding anniversary with a yoga retreat in May.
In March, the couple enjoyed a beach getaway to celebrate Consuelos' 47th birthday. During the trip, Ripa and Consuelos shared sexy photos of each other in their swimsuits, which attracted some body-shamers on Instagram.
During an appearance on Watch What Happens Live with Andy Cohen in April, Ripa and Consuelos said they were confused by response to Ripa's bikini photos.
"It was bizarre," Consuelos told Cohen. "It's like, what else are you supposed to wear to the beach?"
"I don't know what I'm supposed to wear to the beach," Ripa added. "I mean, I don't really know. I wasn't in synagogue. I was at the beach. I mean, if you come up with an option, let me know."
At the time of the backlash, Consuelos directly responded to defend his wife.
"Yes she's wearing a bikini at age 47 and will no doubt wear one for many years to come," the Riverdale actor wrote. "If that offends you in some way, if it triggers you, or some other psychosis you're suffering from, I suggest you get over it and get used to it. To all the males that had something negative to say. I suggest you bring it up with me if ever I'm lucky enough to run into you. I'm going to get back to my vacation now."
Consuelos and Ripa are also the parents of Lola, 16, and Joaquin, 15.