A Queensland family is mourning the loss of an 11-year-old boy who died after sustaining a seizure in his sleep.

Jett Somerhayes-Nixon died on ANZAC Day after failing to wake up after the seizure in his sleep.

His aunt, Lucy Somerhayes, wrote on the family's GoFundMe page that their “Jetty Spaghetti” had autism and was “plagued by seizures over the past few years”.

“But although it wasn't easy, he was the happiest little boy, he loved to sing, dance and make everyone laugh... he was at his happiest if everyone was laughing, singing and dancing with him,” Ms Somerhayes wrote.

“He has now gone on to 'rave in paradise', but his family needs help right now to help with funeral costs and give him the send-off he deserved, and to help support them whilst they try and face life without their young, happy, smiley, singing boy.”

Somerhayes spoke to Yahoo! News about the loss of her nephew.

"It's completely unfair and unbearable that such a massive personality could leave us in such a tragic way," she said.

"It's so incredibly quiet without him."

Jett suffered from 50 to 60 seizures a day, which led to him being hospitalised as well as needing a wheelchair to get around.

However, the family said that Jett hadn't had a major seizure for months before he died.

The family believe that Jett died from Sudden Unexplained Death in Epilepsy (SUDEP), as the family found out the cause of death on Thursday and want people to be aware.

“In general, people living with epilepsy are at a one in 1,000 risk of SUDEP per year,” Epilepsy Australia says.

“In children, SUDEP is an even rarer occurrence with the risk as low as one in 4,500. Most, but not all, cases of SUDEP occur during or immediately after a seizure.”

Photo credits: Yahoo! News