Katie Holmes and Nicole Kidman have formed a friendship due to their previous connection with ex-husband Tom Cruise. 

Kidman and Cruise got married in 1990 and divorced in 2001. The "Mission Impossible" actor then married Holmes in 2006 until 2012.

But after the "Dawson's Creek" star divorced the action movie actor after six years of marriage, she immediately turned to someone who knew what she was going through - Kidman. 

According to an insider who spoke to OK! magazine, being married to Cruise once is a "very unique experience" they both shared.

"Nicole knew firsthand how difficult it was to walk away from Tom and the stress that comes with being married to such a huge star."

Following his marriage to the "Nine Perfect Strangers" actress and after dating Penelope Cruz for three years, Cruise married Holmes just months after they welcomed their daughter Suri. 

Per the source, Holmes and Kidman could also relate to their decision to denounce Scientology. 

"Nicole finally felt free to say her piece," they said. "She grew a lot in the years since her split from Tom and was no longer afraid of being silenced by the church."

In 2018, Nicole Kidman talked about her kids' decision to follow in Tom Cruise's footsteps joining the controversial religion. 

The "Big Little Lies" star said, "They are adults. They are able to make their own decisions."

Isabella and Connor Cruise were adopted by Kidman and Cruise, and both are now 28 and 26 years old, respectively. 

"They have made choices to be Scientologists and as a mother, it's my job to love them." 

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But Katie Holmes is one person who knows about the church that remains tight-lipped on the religious movement. 

Following her split from Cruise, an insider revealed to OK! that Kidman and Holmes spoke a few times, and Kidman's advice for the "First Daughter" actress was to "hang in there." 

"She would tell her that everything was going to be OK and congratulated her on taking such a brave step."

Holmes reportedly appreciated the support she got from the former Mrs. Cruise, with the source dishing, "She has a lot of respect for Nicole as one of the best actresses of her generation and also as a compassionate and impressive human being."

Though both Nicole Kidman and Katie Holmes are from different states, they remain fans of each other, despite not having the time to hang out.

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