Nickie Windram, 36, said she was distraught after the irreplaceable footage of her mother Trisha Farrington disappeared.
Mrs Windram, of Muswell Hill, north London, took the video into a local store, Snap Happy, to be made into a DVD as a memorial to her mother.
02 Apr 2010 Daily Telegraph
But when she went to collect them there was no trace of the video or DVD and it is feared the footage may have mistakenly been given to another customer.
"I couldn't believe it. This video holds the last memories I have of my mum and one of the last happy times," said Mrs Windram, a public relations worker.
"She was diagnosed with breast cancer just a few months after our wedding, so she has always been ill or wearing a wig or something else. This was the last time she was happy and really herself."
The shop has now launched an appeal to find the missing video, believing it was given to another customer by mistake, and has handed out more than 800 leaflets in an attempt to trace it.
The film of Mrs Windram's wedding to her husband Richard, an economist, in Buckinghamshire in 2006 features the only pictures of her with her mother at the ceremony.
Her mother was diagnosed with breast cancer just months later and died in July 2007.
"When we went to collect it we were so upset when they said 'We can't find it' but then admitted they must have lost it," said Mrs Windram.
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