The Smallest People In The World (C4); Extraordinary People: The Boy Who Sees Without Eyes (five):

SHARON'S mother says her daughter was so small when she was born it was like having a doll.

She actually wore dolls' clothes until she was three or four years old. Now Sharon is 43, 4ft 3ins tall and weighs just 34lbs.

She's one of only 100 primordial dwarves in the world. This smallest and rarest type of dwarfism is characterised by severely restricted growth, proportionate limbs and high-pitched squeaky voices.

At 43, she's also the oldest primordial dwarf alive - extraordinary really considering they rarely live beyond their late 20s.

She's come to terms with her condition, building a contented life for herself. Jane Treays' moving, unsensational documentary looked at the lives of five others living in America.

Doctors don't have the answers to the questions that parents of primordial dwarves want to know. None have married, had a child or fathered a child. All doctors can say is that they believe delivery would be fatal.

This doesn't stop 16-year-old Bri telling us she wants to have three kids and adopt another. At 2ft 3ins tall and weighing 16lbs, she's one of the smallest primordial dwarves. Her mother rejected suggestions she should be put in an institution after she was born.

Her younger brother Bradley, 14, has the same condition but wants to be a basketball coach, not seeing his size as a drawback.

Parents have to deal with all the usual teenage hopes, dreams and problems as well as dealing with the condition in the first place. Danny's mother couldn't even say the word "dwarf" after his birth. She practised saying it at home. "I couldn't get the word out, all I could think of was Snow White and the seven dwarves," she said.

Now 16, Danny is at high school but tires easily and he has to go to the canteen ahead of classmates to avoid being crushed.

What's remarkable about the children is how they're learning to adapt to life in the literally big wide world. The equally resilient Ben Underwood is a blind US teenager who says: "I don't see myself as blind, I consider myself as a normal child."

He had his eyes removed at the age of three because of a rare eye cancer. His mother's positive attitude instilled a sense that he could do anything he wanted as she encouraged him to explore the world through touch, smell and sound.

He has $46,000 handcrafted designer eyes - alarmingly, first seen being washed under the tap - but that's not what distinguishes this 14-year-old. He's able to get around without using a guide dog, white stick or even his hands.

His hyper-awareness to sound allows him to navigate using clicks. He picks up echoes as they bounce off things around him. In some ways it makes him more alert to danger than his sighted friends.

We saw him meeting up with another blind man who combines echo location with a cane. He took Ben hiking in a case of the blind leading the blind.