A Medical Certificate stating cause of death wasn't required until 1874.In 1926, an Act of Parliament made it unlawful to dispose of a dead body before a registrar's certificate or a coroner's order had been issued. When was your death?
What was her name? I know you said you have looked for a newspaper account, happy to look in newspapers I have access to.
I'm assuming it was this death:Jane EBENEZER March qtr 1869 Tregaron (11b/60) aged 12.Shropshire Lass has the certificate.