The ACH, which consists of more than 40 children's hospice services throughout the UK, was chosen after the agency's staff voted on which of 10 possible charities they most wanted to help.
Mason Zimbler will help with fundraising campaigns throughout the year and a rebrand in July.
The agency began helping the charity out on a short-term basis last year, helping to design its annual review and giving it all proceeds from its December ball.
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