Thousands Rally to Find Girl's Missing 'Best Friend' Rabbit
PHOTO: Ruby and her best friend Mr Rabbit before he went missing in London this past weekend.

A growing, grassroots campaign is currently underway in England to help a distraught little girl reunite with her beloved stuffed animal that went missing this past weekend on a family trip to London.

Ruby and her "best friend" Mr. Rabbit, before he went missing in London this past weekend. (Credit: Gracie May Photography )

When the girl's mother, Zoe Stewart, realized that the floppy-eared "Mr Rabbit," which had been with her 3-year-old daughter, Ruby, almost since birth, was lost, she quickly turned to her social media followers on Twitter, Facebook and Instagram for help.

LOST!!!!! Lovely people of London please keep your eyes open & retweet if you can, one super upset wee girl :(

- Zoe Stewart (@SimplyRuby) November 17, 2013

This simple plea struck a chord, and thousands of people have joined the search.

As of Monday night, 48 hours since Stewart's first post, the initial tweet has been retweeted more than 1,100 times, and the Facebook post shared almost 3,000. Two British TV personalities - Cherry Healey and Kirstie Allsop - even tweeted about it, local newspapers have written about it and the hashtag #findmrrabbit has begun to pick up traction.

"I think the whole of the U.K. is looking for him," Stewart said in an email to ABC News.

On her Facebook page "Find Mr Rabbit," Stewart explains how the plush toy went missing:

"On Saturday around 6:30 p.m., we left the Flat Iron Steak Restaurant with Mr Rabbit still in hand. We walked slowly around, past BoDeans restaurants over to Oxford street, and caught the tube to London Bridge. We changed at London Bridge and headed to East Dulwich. Mr. Rabbit vanished."

Despite a brief moment of hope Monday that he had been found …

The Internet is amazing!!! We *might* have located Mr Rabbit!! Fingers crossed!!

- Zoe Stewart (@SimplyRuby) November 18, 2013

… it turned out not to be Mr Rabbit after all, but rather a plush lamb

Thought we had a lead on Rabbit there but sadly not (he's still missing :( #findmrrabbit

- Zoe Stewart (@SimplyRuby) November 18, 2013

Mr. Rabbit's disappearance has apparently been devastating to Ruby, who her mother said has gone to bed "in tears" and "sobbed herself to sleep."

Stewart said the rabbit was her daughter's "best friend" who goes everywhere with her. "He was there when she was in the hospital, he was there when she had chicken pox, her first touch, the first time she fell and skinned her knee or bumped her head. He's seen it all."

But now, it seems, he's seeing London.

Tips on Mr Rabbit's whereabouts? Send them here.

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