Firstly son cannot use the TDS of mother to settle his tax dues as the PAN mentioned in TDS deduction would be of mother and tax department would not provide credit of such TDS to son even if he claims the same in his return.
Secondly since mom has earned capital gain income she will have to pay tax on same..she might be having TDS deducted to reduce tax liability. Instead of distributing entire income she should have invested the amount to claim some exemption so that tax liability would have been reduced. After the investment mature she should have distributed.
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