Thank you so much everyone for all your replies. Good to hear that those who have been open from the start are happy.
aloha - you're right, I am just using 'half-brother' etc just to explain, my daughter does just call them her brother/sister.
janh - he's going to come to my house and then we are going to do I don't know what yet. He usually comes about twice a year, goes to buy her a present and then we go to the park or bowling or whatever and then he goes home. I always have to go with then since my daughter doesn't want to go alone with him - she doesn't know him really. I'm sure he would prefer to take her somewhere alone but not yet.
I'm not upset as such, just unsettled by it. Think it brings a lot of uncomfortable feelings to the surface. They live 20 miles away so are never going to be in each others lives much but my daughter already senses, I think, that there is something odd about her dad being with her brother and sister all the time but not her. An it bugs me as well, although, realistically know there is not a lot else I can do about it. It took me 18 months before he ever gave me any money towards her and that amonut (paltry, would pay for 2 days childcare a month) has never gone up in 5 years. My attempt to bring up the subject resulted in him moaning about having no money (although he earns the same or more than me) and since then he has had another child. I can't push the subject because I don't want to jeopardise any relationship my daughter may have with her father's family (which is also complicated - he has half-siblings, his grandad had 'secret' child...) plus his partner rang me once and wanted to know why I wanted my daughter to see her dad and was angry that he was paying any money towards her. I can't do with the hassle of it but I know it's unfair and these visit just bring it al to a head. I have to act so pleasant when we really have nothing in common, part from the obvious, and even then, he doesn't really ask about her, never rings her, never even emails her though she has her own email address and I've suggested a few times that he should. And I must neve reveal any negative feelings I have to my daughter. I hate that when he comes it is always associated with a big gift, she would just like to see him.
This has drifted off the point now hasn't it? I'm hoping that she does get on with her brother, or at least that they like seeing each other. I'm secretly hoping that, one day, they can email each other and at least become pen-pals!
Have to just say that I'm very pround of her though. When I said that her dad was bringing a Christmas present she said that we'll have to get one for her brother since it's not fair if it's just her that gets one - she was born kind I think.