I think certain types of "blood" are: your mom and dad, your sister and brother, your husband or wife, your child.
Had you asked me 2+ years ago that list would have been so much longer, but now.... I don't agree.
I think Some blood is thicker than water. Maybe it's just my family. Maybe I'm the one to blame, but really when I sit and think about the way some of my family has neglected, abandoned, slandered, and avoided me, I've given up on thinking that you can rely on anyone but those that either birthed you, were birthed by the same people as you or helped you birth someone else.