yes I have heard of it, its a type of cognitive behavior modification therapy (some locations call it CBT - cognitive behavioral therapy)where you identify parts of self (parent, Adult, child thinking patterns/behaviors) A person with ego states can have many parentified ego states, Adult Ego States, child like ego states or they can have just one ego state that represents all three thinking patterns.behaviors or even just one of one of the three thinking patterns/behavior patters.

having ego states is different then having dissociative Identity Disorder type alters but it very similar. example with DID the person has to have at least two very special types of alters and with ego states the minimum is one.

Ego state therapy is where everyone is treated like a whole unit, like a family, connected to each other. but each member of the family (ego state) works on what ever conflicts they may have. example if the child behavior pattern in throwing a fit, that ego state needs to work on why they are throwing a fit, recognize the past from the present and understand how to live in the present rather than letting the past behavior thinking pattern interfere.

one ego state I had was a parentified one (one that mimics the behaviors and thinking/beliefs of my parents) was interfering with my parenting my children. through therapy this mindset I was in was able to understand that times have changed. there are new ways to parent children then when I was a child. After that parentified ego state understood and learned to distinguish the past from the present she integrated (became one with me) so that now there is no conflict in my mind with parenting my children.