A video posted to YouTube about a transgender six-year-old has had over four million hits.

The video features Ryland Whittington, who was born a girl but is being raised as a boy by his own choosing.

The seven-minute video was posted online by his family who said that as soon as Ryland could speak "she'd scream 'I'm a boy'".

"She began to show aversion to anything feminine," the family said.  

"She said, 'When the family dies I will cut my hair so I can be a boy.'

"Through tears she asked, 'Why did God make me like this?'"

The family embraced Ryland's gender preference when they came to feel it was more than just a passing phase. 

"We all came to the same conclusion...Ryland is transgender," they said.

As a result, they cut Ryland's hair and changed his clothing. They also stopped referring to him as "she" and instead used "he".

His parents, Jeff and Hillary, revealed not everyone took the news about Ryland's change well.

"We lost a few... but the people who truly matter stuck by us," they said.

Ryland can also be seen thanking his parents at an equality event in California and referring to himself as the "brother" of sister Brynly.

"My name is Ryland Michael Whittington," he said. "I'm a transgender kid. I am six. I am a cool kid.

"I am the happiest I have ever been in my whole life."