My sister told me today I killed my mom

My mom died 11/25/2012. She also had lots of mental problems. I talked to her everyday and was her emotional support. Then her last two monthes alive she set up a family picture for when she was in hospice dying and said it was only blood and my step daughter whose 12 cudnt be In pic. Mok well my sister hates me and is a control freak. she hATES MY STEP DAUGHTER AND TOOK OVER MY MOMS MIND. SHE TOOK INHERITANCE MONEY AND NOW TOLD ME I KILLED MY MOM CAUSE I SAID IT wasn't right to hurt kids