Rugby legend and MND campaigner Doddie Weir has pulled out of an appearance to promote his autobiography due to a mystery 'illness'.

The former Scotland international was scheduled to appear at Pitlochry Festival Theatre for the Winter Words event alongside co-author Stewart Weir tomorrow.

But the theatre announced that Mr Weir would not be attending via their social media sites.

They said: "Sadly, due to illness, we have to announce Doddie Weir will not be able to attend Winter Words tomorrow. Stewart Weir, Doddie's ghost-writer, will still take the session and continue to talk about Doddie's book, his relationship with Doddie, and the process of ghost-writing.

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"We send our very best wishes to Doddie Weir, and look forward to sharing news of the amount raised for his charity from the donations."

Tickets to the event cost £10 with £5 of the proceeds going directly to the My Name'5 Doddie Foundation set up after Mr Weir was diagnosed with motor neurone disease in 2016.

Working tirelessly to raise funds to aid research into the progressive condition, Mr Weir is a regular face at events organised to raise funds for his charity.

On February 1st he attended a gala dinner organised in his honour at former school, Erskine Stewart’s Melville Schools in Edinburgh, which raised more than £90,000 to be split between the My Name'5 Doddie Foundation and the school's Access to Excellence bursery fund.

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Mr Weir's autobiography charts his rise to fame on the pitch from his childhood in the Borders. In it, he speaks candidly about his diagnosis with MND, an incurable condition that stops signals from the brain reaching the muscles.

It was announced earlier this month that Mr Weir's foundation had doubled its donation to the Motor Neurone Disease Association, adding a further £100,000 to its initial contribution of £100,000 previously gifted.