Vatican paper criticizes gay adoption after Italy ruling VATICAN CITY (Reuters) - The Vatican newspaper on Sunday stressed that children should be raised by a father and a mother after Italy's top appeals court granted a gay mother custody of her son, prompting a debate over gay adoption. Italy's Court of Cassation on Friday rejected an appeal by a father who feared his son would not have a balanced upbringing if he lived with his mother and her female partner. The court ruled it was "mere prejudice" to think that a child could not be brought up normally by homosexual parents. While gay rights group Arcigay hailed the decision as a "historic ruling" in Italy, where it is illegal for gay couples to adopt, Catholic leaders were quick to defend the traditional family unit. L'Osservatore Romano, the 151-year-old mouthpiece of the Holy See, on Sunday ran an editorial which sought to play down the ruling of the court, saying that children often grow up in difficult circumstances without a mother or father. "But no one believes that these situations should be created just because in some cases they don't cause damage," wrote Adriano Pessina, director of bioethics at the Catholic University of the Sacred Heart. "The human is the masculine and the feminine ... the monogamous family is the ideal place to learn the meaning of human relations and is the environment where the best form of growth is possible," he said. He went on to reaffirm the Vatican's view that no one has the "right" to children that he said gay couples who want to adopt are claiming. The debate flared up in Italy as hundreds of thousands of people gathered in Paris for a mass demonstration against President Francois Hollande's planned legalization of same-sex marriage. The Vatican has become increasingly vocal against gay marriage and adoptions in recent months. The pope strongly reaffirmed the Church's opposition to gay marriage in December, saying heterosexual marriage had an indispensable role in society. Reporting by Catherine Hornby; Editing by Alison Williams