L.C.
Sometimes God does a really special thing. We are born into the family he gives us. We look like them and sometimes act like them. But, sometimes when he thinks we need a little something extra special he will give us another family. Those are the parents, grandparents, siblings, aunts, uncles, and cousins that are the families of our hearts. They are just as much family and they love us just as much. I am blessed to have both kinds of family. It isn't the dna that counts, but the love. THAT is what makes us family. That has been my experience and if I was in your position that is how I would explain it. It is a gift and nothing less.
As to the family they should probably be told in the nicest of ways to shut up. Dan decides how many children he has and no one else. They should be reminded about little people having big ears.