The inscription on her tombstone reads "Love one another, as I have loved you"
An epitaph is a commemorative inscription written on a tombstone or a commemorative monument. It traditionally starts with "here lies"... One of my personal favourites is François Mauriac's: "Death is the only one of my adventures I will not comment upon."
There is no one-word substitute in English for "son-in-law."
The word you want is florist.
epitaph
Sportsmanship is a word substitute for spirit of game
The word metalworking is one word.
One possible substitute for "their" is "his" or "her" depending on the gender of the person/people being referred to. Another substitute can be "its" when referring to a non-human object or entity.
eat, use
The word that works is idiot.
Elevate
Traditionalist