A poster promoting the Harry Moseley Charity Ball will be unveiled by TV star Ben Shephard later.
It'll happen at 10:30am near Selfridges in Birmingham City Centre.
Ben, took Harry after meeting him during his battle with a brain tumour.
Harry Potter stars Oliver and James Phelps, and Blues legend Michael Johnson, were also expected to join Ben for the launch.
The charity ball, will be held at Birmingham's ICC on August 24 and aims to raise more than £50,000 for Help Harry Help Others, the charity launched by his mother.
Other celebs expected to be at the ball include England and Chelsea star John Terry, Duncan Bannatyne off Dragon's Den and TV presenter Alison Hammond.
Harry's mum Georgina says she overwhelmed by the support:
More than 50 companies in Birmingham have pledged to help out at the event.
Harry died of an inoperable brain tumour in October 2011, after spending his last two years raising money for charity by selling handmade bracelets.