My Aunt Mary told my Aunt Lorraine, at my uncle’s viewing, to stop stroking the my uncle’s over coat (which Mary had advised her to have put on him) because poor Jim was going to need it.
Then about two years later, when a third aunt died, Mary refused to get out of the car at the cemetery because she was so upset that Isabel had been cremated, that she could not watch.
I thought at the time that Mary was just old and not thinking straight, but my sister insisted that it had something to do with my uncle and the Masons. No one else in my family believed anything like that, even the Masons or Eastern Star members.
Masonic funerals are only an adjunct to actual religious services and do not substitute for them in any way. The main idea is to help console the bereaved, letting them know that a group of men they might not have even been very aware of is now dedicated to ensuring that they are helped whenever possible.
In the ceremony, an apron will be draped over the coffin (or some appropriate item relative to the deceased, if cremated) and sprigs of acacia will be strewn. That’s all. The fear does sound unfounded and you should feel confident in reassuring your sister on the point.