chay, thank you so much for your response, it has really opened my eyes! This is very much along the lines I was thinking but of course DH thinks I'm reading too much into everything and comparing the kids too much. I think it's worth having him tested again, particularly as our out of pocket maximum has been reached on our insurance so it will cost us nothing. There's no harm right?

I'm actually wondering if DD is dyslexic at the moment. I've just noticed that she spells certain words wrong consistently (that weren't caught by the teacher) yet excels in reading and language. DH says no because she would be doing X, Y, Z and spelling X, Y, Z wrong like him. I told him that I've read that no two dyslexic people have exactly the same issues and yes, I have heard of stealth dyslexia in gifted children!

Now to persuade DH to get them tested....