 SPOILER: The movie title "C.R.A.Z.Y." has in fact two references.  First, the famous hit song from Patsy Cline (qv), singer whose  father Gervais Beaulieu is "crazy" about. And more importantly, each  letter represents the first letter of the couples sons first names,  in order from the oldest to the youngest (Christian, Raymond,  Antoine, Zachary and Yvan). This fact, never revealed by the father,  is discovered midway through the film by Zac Beaulieu then, after  the end titles, by the viewers.