This is anecdotal but I was told that the practice of renaming or adding to the
name of a child who was gravely ill with the name of a long-lived deceased loved
one was done in the hope the child would recover.
I can tell you that my maternal grandfather was originally named Moishe Chiam.
Moishe was very ill as a child and was given the additional names of Gedalia
Meyer in the hope that the long life of this uncle would somehow pass to him.
When my grandmother would be annoyed with Moishe, she could be heard to loudly
call "Moishe Chiam Gedalia Meyer" and then stamp her foot. My grandfather lived
a joyful life, so maybe the "magic" works.
Researching: DATZ, SAPIRSTEIN (SIPERSTEIN), WALZER, ESCHEN, SINGER(MAN),
SCHNEIDER, GOLDBERG (GRAHAME), LIEBOWITZ