I did a little research (love doing it)and found this. According to Copyright laws in U.S.A. "17 U.S.C. ss 102 (b) " In no case does copyright protection for an original work of authorship extent to an idea, procedure, process, system, method of operation, concept, princible or discovery, regardless of the form in which it is decribed, explained, illustrated or embodied in such work"
Pattern is a procedure, process or method of operation for making a quilt, so it looks to me like Diane doesn't have a leg to stand on!!!