The talented youngster, who raised almost £33,000 for the Sick Kids Friends Foundation last year by selling his art, is to relocate from the family home in Prestonpans, East Lothian, to San Francisco in October.
His father, Ed Henderson, set up the website with the initial aim of raising £100 after Jack said he wanted to help raise funds for the hospital where brother Noah was given treatment.
Now Mr Henderson has landed a new job in San Francisco and is relocating the family.
“We wanted to move and now’s the time before the kids get too big,” he said. “Jack flips between definitely going and definitely not, but he’s quite happy.”