Weddings and family relationships.

Some people have great relationships with their families, unfortunately some don't.
I once performed a ceremony with 28 people in the bridal party and they were ALL family members of various ages (children and grand-children). 
Another wedding ceremony I performed had a security-detail to prevent the 'crazy' family members from crashing the occasion. It had happened before at another wedding, so wow.

Some couples getting married have family members that have passed away.
Pausing at the beginning of the ceremony to light a candle (or similar ritual) is a nice inclusion to remember loved ones lost, but never forgotten.

You may have a distant relationship with your family.
A beach wedding ceremony I performed sometime ago was streaming live overseas to family and friends in Hungary.

Some people believe that when getting married 'young' - that children are expected of the married relationship. 
I am very happily married but we have chosen to have no children. They are just not for the journey we have chosen in our married life. 

When it comes to families...
​Each to their own.