As per Scriptures, the following are the three important duties of a Son (Putra):
1. Following the words of Parents when they are alive
2. Performance of annual ceremony (SrAddha)
3. Performance of pinda dAnam at GayA
jIvator vAkya karaNat pratyabdam bhUri bhojanAt !
gayAYAm pinda dAnAt ca tribhih putrasya putratA !!