Thank you DY.
In one of Rabbi Dr. Avraham Twersky’s books (possibly “From generation to generation”) he writes about how good he would feel when he saw his mother lighting one candle for each person in the family. He realized that there was extra light in the world because of his existence.
I don’t know if there is a specific source for that concept or not, but it’s not the type of concept that requires a source.