Mourning customs in the Regency Era were less rigid than in Victorian England. The excessively strict mourning rules we often encounter in historical novels came about after Queen Victoria’s husband died -- she wouldn’t give up her black mourning clothes and turned mourning into a firmly followed rule of propriety. Her subjects used her example to springboard their own mourning customs. Keep in mind that these are not LAWS for mourning. Any display of mourning was done at a family's or person’s discretion. However, there were social norms, that, if not followed, might raise some eyebrows.