Hmm, I'm thinking about this too. First thing that pops in my mind is your difficult child has manipulated her pretty well. difficult child's need to charm the pants off of those who can help them and also lie their butt's off to gain pity and sympathy from the people they can use, even if its just for sympathy. They need someone on their side, in their corner. So who knows what he said to her about you.
or
Next, why would she give up on her own daughter but fight for someone else's child? Unless, this is her way of gaining a confidant and a friend so she doesn't feel so alone in the matter. Some people put up false fronts about their intentions (I am so concerned about your son and not my own daughter), when in fact they are looking for something else. Maybe she has her own agenda.
or
Final thing, maybe self projection? She is finding herself living through you? Maybe she is so confused, beaten down and twisted up about everything that she isn't even thinking clearly.
