Emmet Mullins will have his first ride in the John Smith's Grand National on Chelsea Harbour, who is trained by his uncle Tom.
The 19-year-old has partnered 31 winners so far during his career and is the son of George Mullins, who runs a horse transport business in Co Carlow.
"It's great to have him on board and he's very, very excited about the prospect," said the trainer.
Emmet Mullins is part of the famous Irish racing family and although there are plenty of jockeys - both past and present - in the ranks, only his uncles Willie and Tony have previously ridden in the Aintree spectacular.
Chelsea Harbour finished ninth in last year's race, with Davy Russell in the saddle, but the Kilkenny handler believes conditions could be going against his horse this year.
"I suppose we could do with a little more rain, but he has run well on good ground, so we can only hope," he added.