in (one's) blood

Innate, as of a skill or quality. All of my relatives are doctors—medical prowess is just in our blood. She knows how to play. Music is in her blood. That type of passion can't be taught—it's just in your blood.

in your blood

COMMON If something is in your blood, it is a very important part of you and seems natural to you, for example because it is traditional in your family or culture. Trilok has music in his blood. `I was born into a family of musicians.' The sea was in his blood — his father had been a marine.

in your blood

ingrained in or fundamental to your character.