Changes Asked in Divorce DecreeCALDWELL — Hearing on a petition to modify a divorce decree was being held by Judge Gilbert C. Norris of Weiser in District court here Thurs.Clark E. Laird, defendant in a divorce action previously granted, asks changes in the decree which awarded custody of children to their maternal grandparents, Mr. and Mrs. Donald G. Hancock.A similar action filed by mother of the children, Mrs. Elnora M. Laird, now Mrs. Elnora Kilbourn, was slated to be heard also today but Mrs. Kilbourn failed to appear in court.