That means, if the child has a strong personality, (s)he can interpret the psychopaths emotionally provocative /abusive acts in a way that (s)he starts to think that the parent has some pain inside, this is why it behaves that way.
As a response to that, the child may accept this situation, and automatically decides to be something like a parent. Emotionally, the child becomes the parent. That means, the child will accept that the environment is just not letting him/her to play, to enjoy life, to be a child. Because the parent becomes the child, so the child needs to take care.
If this mechanism stays "on" - and it possibly will, because the situation can't be resolved until the person understands that the parent's behavior was intentional -, it can lead to a very draining, tiring life, because the person may instinctively acts like a parent who always has that little baby around.
This can play a huge role in DP.