Dorothy Holm Web Mystery
One of the cards show to Ask MetaFilter's users Joanna Holm

When Dorothy Holm was dying of brain cancer in 1994, she left to her grandchildren twenty cards filled with scribbled letters. It was a final message, and a mystery to solve.

Joanna Holm was 11-years-old when her grandmother handed her the puzzle, and twenty years on she still had no idea what it all meant.

"She declined rapidly; she lost a lot of her memory," Holm told Mashable. "She seemed really confused, but she left these cool codes that I thought I would decipher."

After months of trying to crack the code, the Minnesota family gave up – that is until earlier this month when Joanna's father happened across one of the cards and Joanna decided to post it on the web in an attempt to solve the mystery after two decades.

On Monday, 20 January, Joanna posted the cards on Ask MetaFilter, a website for people with questions in need of an answer.

Within 15 minutes she had a partial answer, as someone worked out that the contents of one card which read "OFWAIHHBTNTKCTWBDOEAIIIHFUTDODBAFUOT, AWFTWTAUALUNITBDUFEFTITKTPATGFAEA" was the Lord's Prayer – "Our Father who art in Heaven, hallowed be thy name, etc".

With the religious undertones uncovered, the web detectives soon realised that it was a personal prayer from Joanna's grandmother to her family.

"I think at this point, it's basically a personal prayer of hers, so I don't know if anyone is going to be able to truly decode the whole thing," said Holm.

Several theories as to the potential meaning of some extracts continued. One user suggested that "WARIEH" meant "We all remain in excellent health" while another said it could mean "We are reunited in eternal Heaven".

After twenty years Joanna's family are simply happy to have some kind of answer, and as she said – it's unlikely anyone will completely know Dorothy's final message.

"This has kind of taken on a life of its own," Holm added. "I'm just as curious to see where it goes as anyone else is."

Ask MetaFilter users even thanked Joanna for sharing her story with them, with one user saying: "Many of us enjoy solving mysteries for their own sake, but it's a real honour to help you decipher something so lovely as your grandmother's final good wishes for you and your family."