Oscar Knox begins cancer treatment in US after completing fundraising
Four-year-old Oscar Knox, who was diagnosed with high risk neuroblastoma, will begin his specialist treatment in the US on Monday.
Last week the family reached their £250,000 fundraising target to pay for the immunotherapy treatment.
On Friday, the Knox family left Mallusk to start Oscar's six month treatment plan in Philadelphia.
Oscar Knox won the hearts of people across the world after setting up a twitter account to update people on this condition.
During the Euro 2012 football games a group of Irish fans made a flag with a message for Angela Merkel. Oscar responded by posting his own cheeky flag online, making national headlines.
When the fans returned from Poland they visited Oscar and donated their flag to his fundraising campaign. It sold for 20,000 euros at auction.
In just over three months the family and their supporters have raised the £250,000 needed to begin treatment in the United States.
Oscar has had a number of celebrity supporters including Olympic medallist Paddy Barnes, Westlife singer Nicky Byrne, the late Ulster rugby player Nevin Spence and Girls Aloud singer Nadine Coyle.
Speaking to the BBC shortly after arriving in Philadelphia, Oscar's dad Stephen said the family were "delighted" that the money had been raised.
"We want to thank everyone for their support, it has been incredible," he said.
"We arrived on Saturday to get settled and Oscar will begin his treatment on Monday morning. He is doing really well. It's just like a big adventure for him and his sister Izzy.
Stephen also explained how the treatment Oscar will be receiving will work.
"Oscar will be having immunotherapy therapy treatment. If there is any neuroblastoma left in his body it will hopefully clear all those up," he said.
"It boosts his immune system to fight the cancer if it was ever to come back. It has been proven in trials over here to give an extra 25% - 30% chance of the cancer not coming back.
"It's a six month treatment plan, as long as their are no hitches along the way."
Stephen said that their time in America was going to be a challenge.
"We've just had to set up home here for six months and hope it all goes well. He will be in and out of hospital so often it's not practical to come home," he said.
"It's going to be tough out here, but we just have to get on it and get him better."