Horrifying results after scientist parents raise toddler with chimp in chilling experiment

Luella and Winthrop Niles Kellogg believed they could use their own child in a chilling experiment involving a chimpanzee.

Toddler Donald Kellogg was just 10 months old when he became one of the subjects in the horrifying and doomed research.

The tot was left in floods of tears when he was subjected to hideous trials at the hands of his parents Luella and Winthrop Niles.

The scientist couple believed if they raised the chimpanzee alongside their own child, the animal would become more human - it had disastrous consequences.

The Kelloggs moved Gua the chimp into their home on 26 June, 1931, reports the Mirror US.

The horrifying experiment had to be abandoned nine months later when it was Donald who "became more ape than human".

His parents observed Donald biting, crawling and grunting like a chimp.

Donald was made to sleep in a similar bed to the chimp and the "brother and sister" were spoken to in the same way.

Gunshots were fired in one experiment to see whether it would be Donald or Gua who reacted quicker.

Both the boy and chimp were whacked on the top of their heads with spoons to determine how different their skulls sounded.

The tests were 24/7 and despite being cut short led Winthrop to publishing a book - The Ape and the Child: A study of environmental influence upon early behaviour.

The Kellogg couple were encouraged with Gua's progress, especially physically, but found she struggled to keep up with Donald intellectually after he started to formulate words. The Psychological Review, discussing the conclusion of the experiment, said: "We are told that the study was terminated on March 28, 1932, when Gua was returned to the Orange Park primate colony through a gradual rehabilitating process.

"But as for why, the Kelloggs, who are so specific on so many other points, leave the reader wondering."

They speculated on the abrupt end of the tests, adding: "First, the schedule that the Kelloggs maintained for the nine months was so gruelling that they may have quit for reasons of fatigue.

"Second, they may have wanted to use the time remaining to them on leave from Indiana to prepare the book manuscript for publication. Third, Gua was maturing, gaining in strength and, according to Kellogg, becoming less predictable and more difficult to manage.

"It is possible the Kelloggs feared Gua might inadvertently harm Donald."

It's reported mum Leulla became concerned her son was becoming more chimp than human, leading to the cessation of the tests. However, life continued as usual for a while, with Winthrop earning his keep by studying bottle-nose dolphins at Florida State University.

He passed away in the same summer as his wife in 1972, and tragically their son died just one year later at the age of 43, reportedly by suicide. As for Gua, she was sent away post-experiment, but sadly died of pneumonia aged three just one year later.