A family full of eccentric, weird and sometimes insane relatives. Preferably all of them, but as long as it's the majority of them then it's okay. Commonly it's all of them except one perfectly normal one. Someone may observe their... "activities", but when they confront the family about this, the said family will often have no idea that they are considered to be out of the ordinary. See also Big Screwed-Up Family. In the Blood is the darker version of this. Contrast Turn Out Like His Father. Examples of It Runs in The Family include: