If you are a Christian, why would the phrase "my blood" come out of your mouth about anyone but another Christian?
Your family on earth is merely that: your family on earth. If you believe you have been adopted as Christ's son or daughter, isn't that your family? The other adopted sons and daughters of Christ?
The blood of Christ is the only blood of consequence to us that believe Christ's death on the cross as anything but lore. So, why you say something like "my blood comes first" when talking about your extended family is confusing to me.
Your blood is the other people who choose Christ.