When Katie Holmes began to plan her divorce from husband Tom Cruise, she received support from an unlikely source -- Cruise's second ex-wife, Australian actress Nicole Kidman. Kidman and Cruise were married from 1990 until 2001.

Reportedly, Holmes, 33, and Kidman, 45, have "spoken over the last few weeks," according to US Magazine. An unnamed source says, "Nicole has been supportive, saying she's been through it too and to hang in there."

The calls were supposedly made via a disposable cell phone so that Holmes could ensure the privacy of the conversations. The Los Angeles Times reports that the same phone was used by Holmes to contact lawyers and begin divorce proceedings.

US Magazine reports that Kidman has been a "private friend" to Holmes who offered advice about leaving the megastar actor without becoming distanced from her 6-year-old daughter, Suri. Kidman shares two adopted children with Cruise, Isabella and Connor, but she does not see them often because they chose to live with their father and continue following the teachings of Cruise's controversial religion, Scientology. In fact, sources say the friendship is not a recent one, and that the two women became friendly when Holmes married the Cruise in 2006 and bonded with Isabella and Connor.

In contrast to Kidman, and perhaps due to Kidman's advice, Holmes has received primary custody of her daughter, and will be responsible for the child's education. Currently, Cruise is filming a role, Holmes is in New York with Suri, and Kidman is with her musican husband Keith Urban and their two daughters Faith and Sunday in Australia.