Circumstantial or Urban Legend?

MJ Lastimosa was born in 1987.
Miss Universe 1994 was held in Philippines.
That makes MJ seven years old that time.
I've read at youtube that the "Little Sister" of Miss Italy (Arianna David) was actually MJ Lastimosa who will later become Miss Universe Philippines 2014.



Priscila Perales was born in 1983.
 Miss Universe 1989 was held in Mexico.
 That makes Priscilla six years old that time.
 One comment I've read on youtube says that the "Little Sister" of Miss USA (Gretchen Polhemus) was actually Priscila Perales who later become Miss International 2007.

If they are not those, who are those "Little Sisters" then?