The `Smile` singer - who gave birth to her daughter in November - has remained quiet about the moniker, but her mother Alison Owen has revealed it for the first time on the social networking site Facebook.
Lily married building boss Sam Cooper last year and has remained largely out of the limelight since, enjoying life in her country home in Gloucestershire.
However, she did enjoy a busy Christmas time, with so many family members involved it took her two days to do all the washing up.
Writing on twitter on Christmas morning (25.12.11), she said: "Shall I wait for husband to wake up or can I just get stuck into my stocking without him?"
Then, on December 27, she wrote: "Just finished washing up."
Following the birth of babyEthel in November, Lily - who has given up her singing career to raise her daughter - she thanked fans and well wishers for their congratulations.
She wrote on twitter: "thank you for all the flowers and lovely messages everybody. very touching indeed. nuff luv x x (sic)"