Mom passed away. Have to inventory assets. How do I do it without hurting feelings?

My mother recently passed away. I am the executor of her estate. She shared a home with a live-in companion (they were not married) for 14 years. Mom had an extensive doll collection that I must now inventory and have appraised. I have been putting off doing it because I do not want to hurt my "step-dad" feelings. However, I really have to take possession of it soon. How can I do this tactfully?