[Advaita-l] shrAddha for the departed soul

[Bhaskar YR]

praNAms
Hare Krishna

Kindly pardon me for asking doubt on karma kAnda.  Few days back I went to one vaikunTa samArAdhana for doing the veda pArAyaNa.  After doing the same and receiving the gOdAnAdi dAsa dAna  etc. We explained the karma vidhi in antyeshti like karNa mantra, dahana, asti saNchayana, dharmOdaka, ekOddishta, vrushOtsarga, sapindeekaraNa, abdhivimOka etc. After this one lady came to me asked me a question, if the soul is taking re-birth (punarjanma) and already there in another body at another place, why we should do shrAddha to that departed soul along with pitAmaha, prapitAmaha (in case of father) decades together ??  why we should offer the rice ball (pinda) and expect the soul  to come in the form of crow (vAyasa pinda)?? What is the time span at pitru lOka, whether pitru-s are there forever without taking re-birth in the pitru lOka and every time they come down to take our offerings during shrAddha time??  And asked some more curious  questions related to shrAddha.  I,  using my all intelligence (though myself not sure of my answers) clarified her, it is one of the three ruNa-s, along with deva ruNa, rishi ruNa, that we have to do without worrying about the departed souls rebirth their staying in svarga-naraka etc.  It is the saMskAra vidhi that we have to do with Shraddha for our own betterment  since shAstra (smruti) instructs us to do so. Etc. etc.  Somehow at last I could able to convince her.  But what exactly is the shAstra justification for this repeated shrAddha every year to our pitru-s ??  garuda purANa or smruti texts would give any explanation to these doubts ??  Or with Shraddha only in shAstra vidhi we have to do it??  Please clarify.

Hari Hari Hari Bol!!!
bhaskar