Q. If there is a number of sons and daughters of a deceased father
living together, does each one have to light a separate candle on the
day of the Yohrzait, or is it enough with one?
A.
Kol
Bo (p. 398), quoting Moed Lechol Chai (p. 34), mentions that in
principle one light for all children would be sufficient. However he
adds that when possible it is preferable that each child should light
their own light to honor their father.
Horav
Shlomo Miller's Shlit'a
opinion is
similar
Rabbi A. Bartfeld as advised by Horav Shlomo Miller and Horav Aharon Miller Shlit'a