Crying at a Wedding

I just left my cousin's wedding. It was beautiful, but simple. There was laughter and humor, even from the preacher, but my mom and my aunt were crying--during the ceremony. Okay, I understand when a mother cries because her baby girl is getting married, or, even a son, but, neither the bride nor the groom belong to my aunt or mom. So my question is--Is it okay to cry at a wedding? A wedding is supposed to be happy, joyous, jolly...not weepy! I realize that my cousin lost his dad three years ago, and, maybe it's okay to mention this loss during the ceremony and the reception toast, but crying at a wedding just seems...wrong. My mom says I will understand when I get older. Whatever! On the upside--there was a cash bar, so I doubt that tomorrow, anyone will remember the blubbering little women.