Please could anyone give me advice about my daughters father?

I am going to answer this from personal experience.In my opinion I would not press the issue of your daughter seeing her dad. he has had his chances and blown them, even a kid can see that.If he calls he calls but I wouldn't let him take her as he has shown to be more than a little irresponsible and she doesn't want to go with him.In the US you would be stripped of your parental rights for this behavior( happened to my cousin although his job out of state didn't help and his ex was very sneaky about it and cruel to the family another story all together). As for your daughter's grandparents I applaud them. They don't have to do what they do but they do because they don't want to see her go with out.They should be allowed to see her as well as her half brother. She will thank you when she gets older and they will too. Why punish them for his bad behavior. That's right you shouldn't. As for her name change the school will not let her go by a known as and neither will the doctor until she has had a legal name change. Seeing as your ex will not allow this(because he'll have to sign off on her) your only option is to have him stripped of his parental rights which can take up to a year.Ask his parents to talk with him. Seeing as he is not paying support or keeping his visits( make sure you document all of this you'll need it for court) he really should do it on his own then he would have no legal ties to her. The only problem that I have with this is the fact that his parents have been so good to you. Is it possible he would sign off and then her name change would include a combo of her current surname and that of her new step father? So say if her name is Smith now it would become Smith-Jones for example.That way you aren't hurting the parents that have helped you so much over the years when he has been so unwilling. something to think about.As I said before regardless of what you do let her grandparents and half brother see her but I wouldn't let him take her because of his past behavior and because she doesn't want to go. I wouldn't even tell her that he has a visit coming up or a phone call is expected because if he doesn't follow through it just hurts her and she doesn't deserve that.If she doesn't know she can't be disappointed and hurt by him.