When you say that someone is your own 'Flesh and Blood' you are denoting that they are, or are like, part of your family. The term is also used to refer to mankind in general.
Example of use: “She’s my own flesh and blood; I can’t believe she treated me that way!”
Interesting fact about Flesh and Blood
The phrase 'Flesh and Blood' is ancient, with the first reference being found in print circa 1000 CE in an Old English translation of the Bible, the Anglo-Saxon Gospels, Matthew XVI 17.
