Babs Beverley, one of the twins in the Beverley Sisters, has died aged 91.
Her death, along with that of her older sister Joy in 2015, leaves Teddie Beverley as the sole surviving member of the vocal harmony trio.
Born Babette Chinery in 1927, Babs was brought up with her siblings in Bethnal Green, east London.
The group were one of the most popular acts of the 1950s and '60s, enjoying chart success with such records as I Saw Mommy Kissing Santa Claus.
Their other hits included Little Drummer Boy, Bye Bye Love and the Irving Berlin standard Sisters.
They had their own BBC TV show in the 1950s and were made MBEs in 2006.
The group effectively retired after Joy married Billy Wright, then captain of the England football team, in 1958.
But they reunited in the 1980s and entered the Guinness Book of Records in 2002 as the world's longest surviving vocal group without a line-up change.
Agent Johnny Mans said Babs was diagnosed with cancer in 2013 and had been living in a care home in Brighton.
"She still looked as gorgeous as ever," he told BBC News.
"She will be sadly missed because they were legends in their own lifetime and people will still remember them."
Firm favourites of the late Queen Mother, Britain's answer to the Andrews Sisters were inseparable, dressed alike and had identical blonde hairdos.
The girls shared a bed until they were teenagers and often finished each other's sentences - making it even harder to tell them apart.
Born to George and Victoria Beverley, aka music hall duo Coram and Mills, the sisters initially had modest ambitions. They all trained as typists and Babs had hopes of becoming a policewoman.
But that all changed when they secured a contract to become "Bonnie Babies" in an advertising campaign for bedtime drink Ovaltine.
With support from bandleader Glenn Miller, they became professional singers, renowned for their close harmonies and glamorous lifestyles.
After the war, the siblings were given their own TV show, initially called Three Little Girls In View and later retitled Those Beverley Sisters. It ran for seven years.
In 1951, the trio signed a recording contract with Columbia Records that helped them become the highest paid female act in the UK.
Babs married Scottish dentist James Mitchell in 1963 but the marriage did not last. She died on 28 October leaving no children, according to the Telegraph.