Postman Pat is a childrens show from 1981 Created by the late John Cunliffe about Pat Clifton, a postman living his daily life in Greendale with the residents delievering letters and parcels with his cat, Jess,However like most UK childrens shows it was translated into welsh but not much is known about this dub
Proof that it exists
https://www.amazon.co.uk/Postman-Pat-Sera-Welsh-Language/dp/B00004COX2
https://www.youtube.com/watch?v=nwbjkZxLZNM
https://www.amazon.co.uk/Postman-Pat-Diwrnod-Trafferthus-Language/dp/B00004CQH3