Gant, who works as a vocal coach in Witney, Oxfordshire, after her singing career faltered 10 years ago, said: "I had told my mum not to film me but she did it anyway.
"I'm hugely grateful to my mum for not listening to me because the response I've had since she posted the clip on social media has been so positive and overwhelming.
"People have been saying to me I need to do this and get my music out there.
"The response to the clip has just boosted my confidence.
"I was a promising singer and 10 years ago I was offered a music contract by a record label.
"It promised me everything but when I looked at the contract more closely I was basically signing my soul away and had no rights over any of my work.
"I didn't sign and I gave up on singing, instead turning to coaching other people. I channelled my creativity into helping others but always continued writing my own material.
"Whenever I visited my mum in Lincoln I'd sneak into the cathedral's Chapter House where the piano was and sit down and play and sing my songs.
"No one ever stopped me and I could be in there for hours. The acoustics in the place are amazing. I'd love to pursue my singing career now.
"I've gone from thinking I will never do something with my music other than just for my own enjoyment to feeling now is the time to do something for myself.
"I help other people with their careers for them to perform professionally and now this clip has shown me I should also nurture my own creativity."
Courtney, 51, a theatre producer and writer who has split from Shukrananda's father, posted the 3.36-minute long clip on Facebook.
She wrote: "So on Boxing Day I went to the cathedral with my daughter Shukrananda Gant and to show my two nieces it as they always wanted to see it.
"She found a piano in one of the chapels and said: 'Mum listen to my new song I've just written, it's called In The Beginning'.
"And she doesn't know I recorded it but I just wanted to share the beauty in her voice and because I love her."
Yesterday Courtney said: "We did not expect this at all, she didn't even know I had recorded it.
There's no sound effects, it's exactly as it was seen and heard.
"We've had about 28,000 views which is pretty amazing and with no publicity at all. I only put the video on Facebook for me because I was so proud.
"I've been telling her for years she has a beautiful voice, perhaps now she'll believe me."
