In case of childless couples or of parents whose children are uninterested, they must get the Jeeva Śrāddha (their own antyeshti) done and perform as much donation as possible.
The same has been provided in the Preta Kāṇḍa of the Garuḍa Purāṇa.
When Garuda asks Lord Vishnu about the kriya for childless couples or the absence of persons authorised to perform it, he replies as follows:
When the there is no authorised person, or there is no definite agreement/ consensus (niścaya), then while alive, a person should give Śrāddha for himself.
Chapter 8 verse 10
Oh Garuda, just as wealth buried in the earth comes to use of a person at any time, in the same manner, donation given by ones own hand is received after death. Despite being poor or childless, one desirous of moksha must definitely do his antyeshti kriya himself. Kriya done with even less money still gives everlasting benefit as offering of ghee made into fire.
Chapter 14 verses 8-10
The Jeeva Śrāddha described in the Purana has almost the same procedure as normal kriya, except the starting part where:
- One performs a yajna for Lord Vishnu.
- One calls Brahmins, feeds them, donates cows, (water) and summons the Viśvedevas.
- One must burn a grass figure symbolically, since we are alive.
Then the remaining procedure of summoning Yama, observing aśauca, giving Tilanjali, Daśagātra, all the rituals for one year including ṣoḍaśa Śrāddha and Sapiṇḍīkaraṇa is the same (as per Chapter 8 verse 28-32).
Despite whatever is written above, it is advisable to consult the family panditji or any other knowledgeable person to help with the rituals.
As regards donation, the following has been recommended, with Vrishotsarga carrying utmost importance:
Whatever one gives with his own hands is available to him in the other lokas. Delicious food, cows, land, gold, clothes etc., whatever is given with one’s hands are available to him in whichever yoni he might be.
Chapter 13 verse 19-21
Whatever is given as donation to help in one’s forward journey, taking that, the jeeva goes happily along the great journey. One who does not have these items goes through it in a troubled manner. Knowing this a person should definitely do the Vrishotsarga. A person without a child, who does not do Vrishotsarga cannot attain mukti. Thus a childless person must definitely do this kriya. The sadgati and punya obtained by Vrishotsarga is far greater than that obtained by the performance of Agnihotra and other charitable Yajnas. Hence this is the best yajna and everyone must strive to do it.
Chapter 14 verse 13-16
Oh Tarkshya, sesame (til) seeds, iron, gold, cotton clothes, salt, seven kinds of grains, land and cow are considered as purer than the other. In a Śrāddha one should, along with a vessel filled with sesame seeds, donate a bed (shayyadanam). One should give poor or orphaned people dakshina too. Either a childless person or one with children, whoever does this, get benefit as what a brahmachari gets.
Chapter 14 verses 43-46
[Note: This shayyadanam has been recommended after the Sapindikarana rite]
Thus we can see that the scriptures have provided a solution to do ones own Śrāddha while alive and donate as much as possible so that the benefits can accrue after death, and regular Shraaddha and tarpan are not required.
On a side note, rather than worrying about their sadgati, modern parents must teach their children about the tradition continuing since ages, the same that their own parents taught them. The idea that ‘times are changing’ and ‘today’s children’ are not interested is irrelevant with respect to these basic traditions. If parents make a conscious effort to teach them, children will automatically follow the tradition regardless of location. As the Garuda Purāṇa says in Chapter 14 verse 46-47, one must continue the nitya naimittika karma till one is alive. Shraadha, tirthayatra, Vrata, all these bestow everlasting benefits even later on.