Their devastating discovery came at the register office in Newport, South Wales, a few miles from where they tied the knot back in 1956. The registrar went to fetch the relevant documents, including a copy of their marriage certificate, and returned ashen-faced. "I don't know how to tell you this," she ventured. "But legally you're not married."
The vicar who married them, at St Mary's Parish Church in Risca, by all accounts a conscientious man, had apparently failed to sign the certificate. "At first I laughed" said Mr Evans. "Forty years of living in sin and I've enjoyed every minute of it."
Ironically, his wife, a dance teacher, had always gone by her maiden name, Miss Winmill.
Their daughter, Kathryn Price, 40, is both thrilled and horrified by the news. Ever since she was young, she has wanted to be a bridesmaid at her parents' wedding, and now it looks as if she may get the chance. However, she is less amused by another aspect.
"Dad said `you know what that makes you now ...', I said `oh, don't say that'."
Mrs Evans, 64, wants to have another ceremony for the sake of her two children and seven grandchildren.
"I know that they have been brought up in a different age, when marriage isn't like it was when we got married, but lately I have felt it is not right that we we're not married legally. I would never have lived with someone and neither would Horace."
Their grandson, Greg Price, 10, says he would prefer them to be married "properly". "It feels kind of strange that Nan and Bampy aren't legally married. It feels that they are not as close as we thought they were."
At this, Mr and Mrs Evans shriek with laughter. They have never been closer, as Greg well knows. "The only place Nan goes without Bampy is work and the only place Bampy goes without Nan is to get his pension," Greg says.
Amid all the flights of fancy about whether the second wedding would be white, whether they would have a video of the service and so on, Mr Evans is genuinely concerned about the legal implications of leaving the situation as it is.
The vicar who married them has since died, and the present minister at the church is nonplussed about the prospect of a remarriage.
"He said it wasn't necessary because we are married in the eyes of God," said Mr Evans. "But what about in the eyes on the law? Solicitors and QCs can twist anything these days."
At 68, Mr Evans' health is not good. Eleven years ago he had a triple heart bypass and he is due for another operation. He cannot bear the idea that there might be questions about his wife's eligibility for a widow's pension, should he die.
A spokesman for the Church suggested that the couple seek legal advice. Norman Doe, a lecturer at the Cardiff Law School, said yesterday that the Evans should not worry.
"I don't know of any specific case of these being tackled judicially, but in the light of very basic principles about consent, no court would consider this marriage invalid."Reuse content