The revelations raise questions about why the Legion didn't remove him from teaching morality or speaking publicly about ethics when they knew he had fathered a child.
In a statement, the Legion said it was sorry it hadn't acted 'earlier and more firmly' to remove the Rev. Thomas Williams from his very public ministry as a spokesman, author and television personality.

It said it took responsibility for the lapse, but didn't admit when Williams' superiors knew of the existence of his child.
Williams admitted Tuesday he had had a relationship with a woman and had fathered a child 'a number of years ago' but didn't identify the woman or say whether he is supporting the child, though the Legion said the child is being cared for.
Williams' admission was issued after The Associated Press last week confronted the order with the allegation against Williams, which was lodged by a Spanish association of Legion victims.
The association's accusations, sent to the Legion and Vatican several weeks ago, also named other Legion priests accused of sexually abusing minors.
The Legion has been beset by scandal following revelations that its late founder, the Rev. Marciel Maciel, fathered three children with two women and sexually abused his seminarians.
Maciel died in 2008, and in 2009 the Legion admitted to his crimes. The Maciel scandal has been particularly sensational given that the Mexican-born priest was held up by Pope John Paul II as a model for the faithful, with his priests admired for their orthodoxy and ability to bring in money and attract new seminarians.
The facade, however, began to crumble in 1997 with revelations of his abuse, though it wasn't until 2006 that the Vatican sanctioned Maciel to a lifetime of prayer and penance for his crimes.
Just last week, the Legion admitted that seven of its priests were under investigation by the Vatican for allegedly sexually abusing minors - suggesting that the same culture of secrecy and silence that Maciel used to cover his crimes enabled other priests to abuse children.

Williams, the most prominent priest in the 800-strong order, was the public face of the Legion in recent years: He spoke about Maciel's double life in a February 2009 interview with the Catholic ETWN program, saying the revelations were a 'very, very hard blow to all of us.'
His stone-faced delivery contrasted sharply with that of another Legion priest on the show, the Rev. Jonathan Morris, who was visibly choked up at the revelations of Maciel. Morris subsequently left the Legion and is now a priest in the New York archdiocese.
Williams, the author of such books as 2008's 'Knowing Right From Wrong: A Christian Guide to Conscience,' was the superior of the Legion's general directorate in Rome in the 1990s, but left the high-ranking post to be a theology teacher at the Legion's university in Rome.
His departure from the Legion leadership has never been explained. In recent years, he has taught theology, promoted his books and lectured widely.
His personal website, which lists his 14 books, speaking engagements, articles and appearances as a CBS and NBC commentator, was taken down on Tuesday.
Emails to Williams, who is said by friends to be suffering from cancer, have not been returned.
The Vatican in 2010 took over the Legion after conducting an investigation into the order and the double life of Maciel, who founded the Legion in 1941 in Mexico and oversaw its growth into a large and prominent congregation.
It is now being run by a papal delegate, Cardinal Velasio De Paolis, who is spearheading a process of reform after the Vatican found serious problems with the cult-like group.
Genevieve Kineke, who runs a blog about the Legion aimed at helping those who leave, welcomed Williams' revelations but questioned who knew what and when given that the child is several years old and that at least some in the Legion are believed to have known for years of Maciel's double life yet covered it up to avoid scandal.
'I'm gratified that this has become known, for it couldn't remain hidden without its own toxic effect,' Kineke said in an e-mail. 'With due respect for his privacy and that of his family, details about the timeline are still important - if only to ascertain if more corporate duplicity led to this point.'
She noted that Williams has been a vocal advocate for the Legion 'evidently while harboring his own 'double life.' Either his superiors knew this, and still allowed him to speak, or he abused his freedom knowingly and engaged in grave hypocrisy.'
The accusation against Williams was first lodged by the Association for Help for Those Affected by the LC, a Spanish association for victims of the Legion.
Member Patricio Cerda told The Associated Press that the fact that Williams only admitted to the accusation when the Legion was confronted shows that the culture of cover up in the Legion remains.
'This shows that there is no real process of reform,' but just a process to rewrite the Legion's constitutions, he said. He said that the cases of abusive priests referred to the Vatican were known to Legion superiors more than five years ago, and a year ago to De Paolis.
Most of the allegations concern alleged abuse from decades ago and some of the cases were well-known among Legion watchers.
'What is surprising is how long it took them to recognize the paternity of a child of one of their priests and how much they tried to protect those who abused children,' he said.


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