Nancy asked her fans for help after learning the Twitter tag @ratpackfrank had been verified by website executives as an official account of the iconic singer.
In a desperate plea, she tweeted, "Friends, how do we get rid of the phony but verified Frank Sinatra? That is Not my dad. Help."
After receiving advice from tech-savvy followers, she then sent a message to Twitter officials to strip the unauthorised account of its 'verified' status.
She wrote, "Attention @Twitter The account @ratpackfrank is not authorised and using my dad's name Frank Sinatra without permission. Please unverify."
The 'My Way' legend died in 1998.
