5 year old telling lies to absent dad about brother

[froggies]

my partner and I split up about 6months ago, we have 2 girls together, age 5 and 2 1/2, I also have a son age 15. We got together when my son was 2, but since we split up only the girls have contact time with dad (who lives very close). for a while shortly after the split my son was unnecessarily (but understandably) physical with the 5 yr old, particularly when she goaded him. We have had outside help for him to help him deal with his anger, and I have seen a real improvement.
We have just come back from spending a week away with members of my family, and although there was the usual bickering and arguing between them all, it was a pretty good week. Although she seems to have taken to biting him -he did not lose his temper with her- and just before we were leaving the 5 yr old got hurt when they were playing a chasing and hiding game, she blamed her brother, but on investigation it turned out to be an accident. (thankfully a cousin was also there!)
This afternoon the girls went to see their dad, and when they came back he told me that she had said her brother had been hurting her (this is now the third time she has said this, and the first time that I am sure she is manipulating the truth). With the added comments of 'just to make sure you are aware'.
I spoke to her, and it appears that they had all been watching tv, and she had said that so that dad would cuddle her because he was cuddling her little sister.
The problem I have is that my partner always accused me of favouring my son over the girls, and in particular over the 5yr old, and even if I tell him that she is manipulating him, he is not likely to believe me or to help me to work towards preventing her from doing it again. He never did before we split, it is highly unlikely he will parent in a co-operative way now.
Does anyone have experience of this kind of thing? What did you do?!
Cheers.

He sounds like my ex in that he is always looking for something to be critical about. Try not to let him get to you. You know that you are in control of the situation and it doesn't matter what he thinks.

Is it worth having a chat with your 5 year old. Ask her what she said to daddy about her brother. When did her brother hurt her etc. If she is telling lies and she realises this is getting back to you then perhaps she might not continue.

gvien the back ground you need to be really sure that the 15 year old is not doing anything untoward or inadvertently hurting the younger one. she may ahve meant an accident - but which accident?

talk to your DS. see if he can shed some light on this. but dont completely dismiss it - you cant watch them all the time...

i am not sure i do understand why he would be "physical" towards his little sister? why is that understandable? what did he actually do to her? what do you mean by "physical"?
i would want to be really sure there is no rough play going on...she bites him - what does he do (out of your eye sight) ?

On this occasion I am absolutely sure that he didn't do anything. He was hiding in a wardrobe, her and 2 others had chased him, she opened the door and banged herself in the face with it. She told me he had poked her in the eye. He told me she had opened the door too hard and he hadn't touched her. I think perhaps he had been hold the door inside, but he wouldn't have known which child was trying to open it from the outside. The cousin confirmed that he had not touched her.
Her standard behaviour is to initiate an interaction, then at some point scream that he has hurt her, some times this has been the case... Holding her arm to stop her hitting him, then squeezing when she keeps trying to hit him... Kicking back when she has kicked him....I have also seen her walk into a room where he is, and scream that he has hit her when he was on the other side of the room.
In the past it would have resulted in him being sent to his room with a big row and some form of punishment, and her getting cuddles. On the occasions when I suspect he didn't touch her, he would have had a row anyway, which usually ended in him doing something to get back at her afterwards. He has told me quite candidly that he feels dad would still have loved him if she hadn't been born.
When I say understandably, I mean that I can understand why he has felt the need to react in this way. It does not mean that I condone or accept it.
Since we split up I am sure there was a period where he was hurting her when he thought he could get away with it, I suspect because the threat of a clout round the head had been removed, he thought it would be safe to 'get his own back'. I am fairly confident that this has stopped. Obviously I can't say I'm positive, but there has been a lot less of her screaming at me that he has done anything, and it was always a screaming, they love me more than you and I'll prove it kind of episode.
I have also witnessed both when he knew I was watching and when he didn't, incredible patience on his behalf when she was pushing his buttons. This was even remarked upon by my dad last week. I suspect the biting is an escalation on her behalf, he isn't rising to the usual stuff so what else can she do to get him to shout and get told off?
Her behaviour in my home I am sure I can work through in time, but I am concerned that she is using him as a tool to get attention from her dad. And what he may do about it if she continues.