Three older sisters: Tamera (born c. 1968), Holly Ann, and Nancy Kay, Mrs. Blaylock (born c. 1975). One older brother: Martin Joseph, Jr. (born 1970), who works as a lawyer in Ohio.
The first movie she ever saw was E.T.: The Extra-Terrestrial (1982).
Was lined up to have a 3 episode guest spot on "Friends" (1994) but had to pull out due to scheduling conflicts.
Her favorite movie is My Best Friend's Wedding (1997).
Auditioned for the role as Buffy Summers in the series "Buffy the Vampire Slayer" (1997), but was too young.
Bought a Wilmington, North Carolina townhouse, while filming "Dawson's Creek" (1998), and lived there for ten months of the year.
Auditioned for the role of Ellie Christianson in Wicked (1998), but Julia Stiles won the part.
Sang Eponine's theme song, "On My Own" from Les Miserables, in an episode of "Dawson's Creek" (1998).
Noisy underground British artist 'Firexit' has two songs with references to Katie, one called "K H" (Katie's initials) and a song called "The reason I can't have her" featuring samples of Katie singing 'On my own' from a "Dawson's Creek" (1998) episode.
Deferred attending Columbia University twice, but finally took a single photography class in the summer of 2000.
Her fantasy role was playing Sydney in Scream 3 (2000).
Ranked #35 in Stuff magazine's "102 Sexiest Women in the World" (2002).
Turned down the lead role in 40 Days and 40 Nights (2002), due to scheduling conflicts.
December 2003 - She and Chris Klein are engaged.
Engaged to actor Chris Klein December 2003 - March 2005. They were together for five years.
Almost cast opposite Patrick Wilson (her co-star on Broadway's "All My Sons"), in the film version of The Phantom of the Opera (2004) as "Christine Daae", but was considered too old to play the part.
Engaged to Tom Cruise as of 17th June 2005.
Has worked with two Batmans. In Batman Begins (2005), she works with Christian Bale. Her previous film was First Daughter (2004), in which her father, the President, is played by Michael Keaton.
Ranked as #72 in FHM's "100 Sexiest Women in the World 2005" special supplement. (2005)
Named #22 on the Maxim magazine Hot 100 of 2005 list.
Katie and Tom Cruise became the parents of Suri Cruise on April 18, 2006 in Los Angeles. "Suri" weighed 7 lbs. 7 oz. and was 20 inches.
Named #90 in FHM magazine's "100 Sexiest Women in the World 2006" supplement. (2006).
On November 18, 2006, married Tom Cruise at the Odescalchi Castle in Lake Bracciano, Italy in front of family and friends. Lots of celebrity guests included Will Smith and Jada Pinkett Smith, Brooke Shields and Chris Henchy, Richard Gere, Victoria Beckham and David Beckham, Jennifer Lopez and Marc Anthony, and Jim Carrey and Jenny McCarthy, John Travolta and Kelly Preston, Jenna Elfman and Bodhi Elfman and Leah Remini.
Participated in and finished the New York Marathon in 2007.
Auditioned for the role of Carla Albanese in Nine (2009), but Penélope Cruz was given the part instead.
Katie's brother-in-law Joseph Jeffrey Fretti, the husband of Holmes' eldest sister Tamara Holmes, was found dead on 12 April 2009 in his mother Shirley's home in Sarasota, Florida. He was 48.