In our area, it's pretty common for the family to establish a memorial fund for the benefit of some organization or charity that the deceased member was active in or supported.......American Legion, Hospice, cancer society, church fund, whatever. Occasionally, the memorial will be listed to the family, but not very often. Sometimes in the case of a young adult who leaves a family, the memorial will be designated for the children's education. It seems to work out pretty well, and no, I don't think that a memorial contribution is mandatory when sending a sympathy card.