Final rites of the mother of Adi Sankara

[Harshit Shrivastava]

Respected Scholars,

Pranam to all.

Upon searching that how can Adi Sankara, being a sannyasi, can perform final rites of his mother, I found this:

"His Holiness observed that Sri. Sankara never did anything against the sAstric
injunctions, and such an observation of Him doing the last rite in spite of
being a sanyAsi was not appropriate. Based on “viswEswara smrti” (prescriptions
and injunctions for sanyAsis), a sanyAsi who is born as the *only child* for
his parents should perform the first day rites (out of the 10 days) for his
parents. His Holiness added that Sri. Sankara did not go against the sAstric
injunctions anytime during His life."

Source:

http://www.advaita-vedanta.org/archives/advaita-l/2007-April/018646.html

Now coming to the point, this "Visweswara Smriti" is perhaps the "Yati Dharma Sangrah" of Visweswara Sarawati published by Anandasharama Sanskrit Series Vol. 60, which is available on internet for download and also available for purchase.

I request the scholars to please help me find the exact verse from this treatise to confirm and check the matter discussed above.

Also, if this special rule is really applicable to the "only child" of the parents who renounced the world, is it actually applicable to the "only male child"? Means what if the parents have a son and a daughter, and still this rule is applicable in this condition?

Regards,
Harshit.