What are some examples of the theme "Mutual sorrow can serve to unite and inspire" in Stave 4 or 5?
Stave 4 of The Christmas Carol describes Scrooge's encounter with The Spirit of Christmas Yet to Come, including an observation of the Cratchit family shortly after Tiny Tim has died. Mrs. Cratchit and the girls are sewing; exactly what they are making is not identified, but Bob Cratchit comments on the speed and dedication with which they are working and says they will be finished with their work "before Sunday." The implication is that they are sewing the clothing in which Tiny Tim will be buried on Sunday.
Later, Bob expresses his certainty that all the family has learned and will remember the example of Tiny Tim and will conduct their lives in the same manner.
when we recollect how patient and how mild he was,...we shall not quarrel easily among ourselves, and forget poor Tiny Tim in doing it.