Thank you tibby and sirzy
and good to see you again floundering you helped me a huge amount on a thread under a previous name a while back 
My son came to me feeling 'differently' when he was 7, I did the whole denial thing, the 'it's just a phase' thing, but I could see him becoming more and more withdrawn, introverted and ashamed of himself.
We had another year and a half of talking, then going to professionals, getting help through various sources, and the minute he realised I was taking him seriously he was like a different child.
He has now been living as a male for over a year. His dad, grandad and granny have disowned him, I've had social services called on me several times, and I have had to move hundreds of miles away and have lost people I regarded as friends because I haven't dismissed my son's feelings and people are confused and upset and embarrassed by that.
Despite everything he has been through he has never been happier. He is getting the help he needs, the support he needs and now that he is on puberty blockers he can relax and take the time to make the choices that are right for him.
He has been diagnosed with gender dysphoria of childhood, when he reaches 15/16 he will, if he continues to feel as he does, be diagnosed with gender dysphoria and will be able to choose for himself whether he wants to continue with hormones etc.
Nobody is encouraging him, the clinic he attends and his school and I are all very open and accepting of the fact he may very well change his mind, and my son knows this. At the moment he feels, very strongly, that this is how he wishes to be and I am going to support him whether he feels that way for another week, month or a lifetime.
To compare the way my son and other trans people feel to wanting to walk backwards or be an animal is, again, insulting.
If your child comes to you telling you they hate themselves, they are in constant tears over the changes that will happen to them, even flinching when you say their name because it doesn't feel like them would you really just dismiss it?