Marriage, money and children are the keys to creating a happy life - but only at certain points, says a psychologist. In order to live a happy life you should have money, but not too much. Get married but have lots of sex and talk as much as you can and don’t have children. It may sound strange but these are the advices of Harvard professor of psychology, Daniel Gilbert to lead a happy life, according to News. com. au. According to Prof Gilbert, his mother had always told him that marriage, money and children were the keys to creating a happy life - but he discovered she was only \"partially\" right. He found that people who are married were happier than other people, because they were healthier, had more sex and tended to live longer. But the happiness generally only lasted between eight and 15 years. After this point couples had to work hard to keep the spark, and their happiness, alive. Money was also a key to happiness, but it actually depends how much you have. Prof Gilbert said that the happiest people earned between 50,000 dollars and 70,000 dollars and often gave money away to help others. He also said that people who earned more than this eventually became unhappy because they were spending the money on the \"wrong things\". Being creative, relaxing and spending time with loved ones kept people happy, while working all the time made people miserable. But children can bring unhappiness to your life. Prof Gilbert said that even though parents spoke \"glowingly\" about their offspring, in reality raising children made people increasingly unhappy. \"Once people have kids, there’s a downturn in happiness,\" he said. From : ANI