Companion Care Needed

Seeking companion care near Burbank for my sister who is 73 and suffering from mild dementia. She lives alone, does not drive or use the stove. We need help picking up groceries once a week and possibly walking a few blocks to have coffee or lunch a couple of times a week. I am her only close relative and I work. She needs more social interaction than my daily evening visits. Also, it would be a nice break for me to not have to visit every day. She goes on a couple of walks alone every morning and afternoon. She is very active. She does not need any help with grooming or dressing. She is a retired writer, but still dabbles a bit in the field.