"... while I sing you a song about GEF THE TALKING MONGOOSE ...."

Wiki:

Gef the talking mongoose was a talking animal that was reported to inhabit a farmhouse known as Cashen's Gap near the hamlet of Dalby on the Isle of Man. Opinion is divided on whether Gef was a poltergeist, a strange animal or cryptid or a hoax.

In September 1931, the Irving family — James, Margaret, and daughter Voirrey (13), claimed to hear persistent scratching and rustling noises behind their farm house's wooden wall panels. At first they thought it was a rat, but then the unseen creature began making different sounds, sometimes spitting like a ferret, growling like a dog, and gurgling like a baby.

The creature soon revealed an ability to speak and introduced itself as Gef, a mongoose, and claimed to have been born in New Delhi, India, in 1852. According to Voirrey, who was the only person to see him properly, Gef was the size of a small rat with yellowish fur and a large bushy tail (the Indian mongoose is in reality much larger than a rat and does not have a bushy tail).

Gef variously claimed to be "an extra extra clever mongoose", an "earthbound spirit", "a ghost in the form of a weasel", and once said "I am a freak. I have hands and I have feet, and if you saw me you'd faint, you'd be petrified, mummified, turned into stone or a pillar of salt!"

He had many characteristics traditionally ascribed to poltergeists in that he had an uneven temper, threw objects at people, and made exaggerated claims about his powers.

Gef remained friendly towards the Irvings, and joked around with them, though he supposedly went too far one time when he pretended to be poisoned. Gef also supposedly bothered the Irvings' neighbours, spying on them and reporting back to the Irvings. Gef was also known as "The Dalby Spook". James Irving kept diaries about Gef between 1932 and 1935, these diaries, along with reports about the case, are in Harry Price's archives in Senate House Library.

The story became popular in the tabloid press, and many journalists flocked to the Isle to catch a glimpse of the creature ...

... The story was widespread throughout Britain in the early 1930s due to extensive press coverage, but apparently no one other than the Irvings ever claimed to have heard Gef speak, or even saw him (though some neighbors claimed to have heard "strange noises" outside their homes).

The only physical evidence cited in support of Gef's existence would appear to be a series of footprints, none of which were identified as those of a mongoose, while a single photo said to show Gef exists.

Voirrey Irving, who took Gef under her wing, is at the time of writing still alive and living in the South West of England.