Transmission to nominee's account

Hello,

I am just posting the query again, since there has been no reply. Experts, please apply  your mind!

After the demise of my mother, some shares have been credited to my demat account, since I was a nominee. I plan to sell these shares, and hand over the proceeds to the legal heirs according to the will.

1. Can the capital gains tax arising from the sale of shares be paid from my mother's account, or is it the liability of the nominee or the legal heirs?

2. Will there be any tax payable by the legal heirs on the proceeds of the shares?

Thank you.