Want A Happy Marriage?

According to new research out of Scotland, if you want a happy marriage, have children.  Researchers say the more kids, the merrier the marriage!  However, they say that this only works for married couples.  They say Couples who aren't married, even if they are in a committed relationship and live together, don't find greater happiness through children.

I don't quite know what to think about this.  I have three children and am so happy with my husband...today!  I know people who have lots of kids and are unhappy.  I have a problem with generalizations.  I also know people who aren't married and have children who are happy.

What's your recipe for happiness?