Cancellation of Settlement Deed between mother and son

1.Son (Married and has a Kid of 3 years) who works out of India buys 2 apartments in Mother's name. 2.Son buys 2 properties for mother and gets it registered in mothers name from his own income while working abroad. 3.Son requests mother to do a settlement deed from Mother to Son after 10 years. 4.Mother does the settlement deed to Son as requested. 5.Settlement deed gets registered from Mother to Son one way as Son is abroad. 6. Son has not yet signed the settlement deed yet. 7.Meanwhile Son falls sick abroad and departs from the world. In this scenario, A. Is the settlement deed from mother to son one way still valid? B. Can Mother cancel the Settlement Deed registered to Son one way and keep the property with her? C. Does both Properties get automatically transferred to Son's Wife as Son bought both properties in Mother's name from his own income even when Son has not signed the Settlement Deed in India? If some one could reply for these queries it will be helpful.