Thumbelina, a five year old dwarf miniature horse, slides underneath the pasture fencing at Goose Creek Farms in St. Louis, MO on Fri. October 3, 2006. At 17.5 inches, she is the smallest living horse in the world, and holds the record for the smallest horse in history. [AP]

ST. LOUIS - At just a hair over 17 inches tall, the miniature horse is more inclined to walk under fences than jump them. And her owners have sheltered the mare from ever gaining "circus-sideshow" or "one-trick-pony" status. As the world's smallest horse, 5-year-old Thumbelina, weighing in at 57 pounds, has a bigger mission: to raise $1 million for children's charities this year.

Handler Michael Goessling, son of miniature horse farmers Kay and Paul Goessling, says Thumbelina is the ideal child advocate. Her name comes from the Hans Christian Andersen fairytale of a woman the size of a thumb.

"When kids meet her in person, they want to talk to her and know what she likes and dislikes," Goessling said. "It's amazing because she is so loving with people. She craves attention."

In the months after being named "World's Smallest Living Horse" by Guinness World Records last summer, Thumbelina has certainly not been short on attention.

She's been showered with praise on the television talk-show circuit. The flow of schoolchildren who visit her is constant, and many leave with coloring books dedicated to the Goessling family pet.

"I'll have her out for hours. She's so mild mannered, everything just seems to brush off her shoulders. There have been 100 kids around petting her and she'll take a nap," Goessling said.

When Thumbelina travels the country this year, she'll do so in style -- in a recreational vehicle that's her converted stable on wheels. Goessling calls it the Thumby Mobile.

An upcoming "Thumbelina Children's Tour" is expected to include stops in the 48 contiguous states at children's hospitals, schools, summer camps, fairs, horse shows and charitable fundraisers.

At Goose Creek Farms, the Goesslings breed miniatures for sale and for horse show competitions, a hobby that's brought them numerous ribbons for more than a decade.

But Thumbelina's special. "We don't want to make a penny off of her," Michael Goessling said. "We never have. There will never be another Thumbelina."

Most of her days are spent playing with like-size farm dogs. She even sleeps in a dog house.

The family calls her a "miniature-miniature" and genetically she's a dwarf. Rules of nature say it's a bad idea for her to reproduce, Goessling said.

Thumbelina often avoids the company of her taller, but still unusually small counterparts. Of the 40 or so miniature horses stabled on the ranch, most are more than a foot taller than Thumbelina.

The tiny horse and her charitable foundation have helped raise about $10,000 for children's charities since she gained World record status as the smallest horse ever recorded, at 17 1/2 inches at the withers.

When a Guinness official came from London to certify the record, a photograph was taken of Thumbelina and the world's largest living horse, Radar, a Belgium Draft horse from Texas standing at 6-foot-7 -- about 40 times larger than Thumbelina.

She wasn't intimidated.

"I got the impression that Thumbelina wasn't so keen on sharing the limelight with the tallest horse at all," said Michael Whitty, who's in charge of Guinness' Picture Media.

The picture will appear in the 2008 World Record book to be released this fall.