Happy to. Here is a definition from Wiki to help:
Identified patient, or "IP", is a term used in a clinical setting to describe the person in a
dysfunctional family who has been unconsciously, or sometimes consciously, selected to lay blame upon to draw attention away from the family's true inner conflicts, true problem behaviors, and their perpetrators. The identified patient is a diversion and a scapegoat. This person, often a child, is "the
split-off false carrier of a breakdown in the entire family system," which may be a
transgenerational disturbance or
trauma.[1]
Essentially, the IP allows the family to continue to function in its’ dysfunction by taking all of the blame/frustration to distract from the real issues at hand.
Many children who are IP’s also take the role on and fulfill it, even if they weren’t problems to begin with. While I graduated from high school with a 4.6 and was a model student, dancer etc at home I was an angry, sullen, miserable child who developed a raging heroin addiction. I have one brother and three step siblings who could do no wrong. I moved out at 17 and never went back. Does this help?