It appears she had a heart attack, all very sudden and over very, very quickly.
The Boy was most distressed, and still gets sad of a morning when she isn't there to be fed. She was his cat now that he was finally old enough to start having that responsibility.
We will be getting a cutting from the family rose bush from my parents at Easter to plant in the garden for her and I think The Boy likes that idea very much.
It's still heart breaking though to hear our 'big' cat crying for her of a morning. She walks around the hallway and kitchen looking and looking, and then goes forlornly back to her breakfast. She does this at least twice and then again throughout the day. Lots and lots of cuddles for her and everyone is treating her extra special.
So rest in peace our little baby Doofie cat. 14 March 2001 - 13 February 2013. Love you lots baby girl.