Auto loans over 60 months are not the best way to finance a car. And yet, 43.5% of new-car buyers in the third quarter of 2015 took out loans of 61 to 72 months, according to Experian.
DNA Tribes is correct that siblings can and do have very diverse DNA. Your autosomal DNA is a random subset of your mother's and father's DNA (50% from each parent). Two siblings will not have the same results for the same reason that they do not look exactly the same. They do not get the exact same 50% from each parent. Even identical twins don't have exactly the same DNA (only almost exactly the same).
First, understand that offspring get 1/2 DNA from mom (maternal DNA) and 1/2 DNA from dad (paternal DNA). Both girls have 1/2 DNA from mom A. and 1/2 from dad A. The Brown children and Charles children are first cousins. They have 1/2 of their DNA in common (Anderson DNA). First cousins share a common ancestor one generation back. The Brown and Charles children share common maternal grandparents (the Andersons) one generation back. The David children have: 1/2 Brown DNA and 1/2 David DNA. The David children have (1/4 A. and 1/4 B.) DNA from their mother.