Katie Holmes ended her marriage to Tom Cruise because she was concerned he wanted to send their daughter to Scientology camp.
The former Dawson's Creek star filed for divorce from Cruise - who is a devotee to the religious cult - after five years of marriage last week. It has been reported that Holmes was concerned Cruise wanted to place their six-year-old daughter Suri with the Sea Organisation.
The chance that Suri may be forced to attend the camp, which has classes on ships and on land, was reportedly behind her move to file for divorce.
Members attending classes on the ship are required to commit themselves to the quasi-religious sect and are allegedly asked to disconnect from any non-believers.
A source told TMZ.com: "In the end we're told Katie felt the only way to prevent Suri from joining the Sea Org ship was to file for divorce and seek sole legal custody."
Former members have described the "school" as a military-style boot camp where members are expected to work for more than 16 hours a day.
However, the main Scientology headquarters are in California at a multi-million dollar compound called Gold Base.
Former members claim the 500-acre site has a bunker, trained sniper guards and a trailer called "The Hole" where people are punished.
Members are also encouraged to pledge their allegiance to the religion for a billion years when they join.
However, a lawyer representing the cult has claimed no one under 16 is allowed to join the cruise liner, adding "consent of both parents and/or all legal guardians" must be given before anyone is allowed to board.
"There is no truth whatsoever to the TMZ.com report (or any other report) that the Church of Scientology has sent anyone to follow Katie Holmes," lawyer Gary Soter told AFP.
"The allegation about a six-year-old joining the Sea Org is similarly untrue."
Despite Katie's fears, it is believed Tom will "move heaven and earth" to ensure his daughter is brought up a Scientologist.
A source said: "Tom believes Scientology changes people's lives for the better and, obviously, he wants what is best for his children.
"Tom will move heaven and earth to ensure Suri stays a Scientologist, at least until she is of an age to make a decision to leave on her own accord."