Is this it?
There is a pattern by that name on the Fon's and Porter website, not sure it's the same as what your DD is looking for or not. I Googled 'Imperial Diamond Quilt Pattern' to find it. Good Luck!
No, wish I did. My daughter saw it somewhere and has been looking for a pattern ever since. I'm excided she actually wants to attempt this. So far, all she does are squares and rectangles :-)
do you have a pic?