S4C has announced a special documentary, Mari Grug: Un Dydd Ar y Tro, which will follow the journey of TV presenter Mari Grug following her cancer diagnosis. Driving a pink tractor, Mari recently led a cancer awareness tractor run in Pembrokeshire.

The programme will air on S4C on October 26 at 9pm, during Breast Cancer Awareness Month.

Since her diagnosis, Mari has become an ambassador for the charity Cancer Research Wales.

The commission was announced by S4C on the same day as a tractor run, organised by Midway Motors, to raise money for the charity. Ahead of its airing, the presenter, who is a familiar face to S4C viewers as one of the hosts of Prynhawn Da and Heno, took part in the tractor run on Saturday, August 16.

Driving a pink tractor, a colour associated with cancer awareness, Mari led the vehicles for part of the journey around Crymych, Mynachlog-ddu and Maenclochog, in Pembrokeshire.

Mari said she was grateful for “all the care” she is receiving.

“Being part of the tractor run in my local area with the rural community, which has been such a support to me and my family during the last two years, is very special," she said.

"I’m very grateful to Midway Motors for letting me join them and to T Alun Jones for trusting me with the pink tractor!

“I hope the programme will show that a diagnosis of metastatic cancer does not mean that life stops and changes completely.

“Also, I would like to see the programme encourage people with a history of cancer in the family to have conversations about their options in order to prevent the illness from causing further damage.”

Shon Rees from Midway Motors, who organised the run, said: “We’re very proud to be part of this special day with Mari.”