Born to Be Different (Channel 4, 9pm)

FIFTEEN years ago, Channel 4 embarked on an ambitious project to follow the lives of six remarkable children who were all born with disabilities. Now, the youngsters are 16 and those taking part in the programme have been reduced to five, following a decision by one family to withdraw. Those of us who have followed the series from 2003 will spot that Nathan, who has Down's Syndrome, appears to be missing.

The first episode covered the youngster's three years from birth. Since then, Channel 4 has broadcast four more updates, showing how the children and their families have dealt with the challenges they have faced over the years. As a parent of a disabled young man, I'm obviously biased about the merits of such programmes, but I do hope it has helped to give audiences an insight into some relatively little-known conditions and the problems they can pose.

The five teenagers are facing added complications. Like many of his peers, William now has a girlfriend, who he says sets his "heart beating". However, he also has tuberous sclerosis, a condition that causes tumors to grow anywhere on his body, in addition to autism and severe learning difficulties.

He's developed a life-threatening tumour on his kidneys, and his parents fear that unless they can persuade the NHS to give him the £30,000-a-year-drug treatment needed to shrink it, he could suffer a catastrophic bleed.

This first episode also catches up with Zoe, who has arthrogryposis, a condition that severely affects movement in her limbs. Despite being different to her friends, she's grown up happy and confident, but as a teenage girl, she's also prone to feeling self-conscious. When he headmistress encourages her to put herself forward as head girl, Zoe can't help feeling nervous about the prospect of making a speech in front of her year group.

Finally, we catch up with Shelbie, who has genetic disorder than means she's severely mentally and physically disabled. Over the years, her health has deteriorated to such a degree that doctors have advised her mother Vicky to consider letting her go.

Most parents will find it hard to imagine being in such a difficult position, and Vicky has always fought for her daughter's right to life. Shelbie is now facing a new problem because her bone marrow is failing, and she will require repeated blood transfers just to stay alive, creating a big impact on her quality of life.

Vicky has to confront the uncertainty of her daughter's future, saying: "To expect her to be here until her adulthood is maybe wishful thinking... but I can't imagine life without her."

As with previous editions, it may not always make for easy viewing, but the programme includes the joys as well as the heartaches that these families have experienced, and reminds us all that there is always someone worse off than you.

Back in Time for the Weekend (BBC2, 8pm)

THE Ashby-Hawkins family enters the 1990s, a decade where new technology starts to dominate their leisure time. Twelve-year-old Seth finally gets his hands on a Game Boy and games console, while the arrival of the internet and a mobile phone marks the start of how many spend their spare time now. Steph and Rob try out line-dancing, and fitness star Mr Motivator puts them through their paces. Tommy Walsh and Linda Barker also turn up to help the family give the house and garden a 1990s makeover. As ever, Giles Coren is your host.

Happy Valley (BBC1, 9pm)

SEAN becomes prime suspect when Leonie is raped, and the authorities believe he could be responsible for the string of murders Andy and the team have been investigating. Meanwhile, John has to think fast when he's asked why his number was on Vicky's phone, and a gift for Ryan on his tenth birthday reminds Catherine that danger may be closer than she thinks. Elsewhere, Daryl takes action when he is confronted by the three lads who have been bullying him. Crime drama, starring Sarah Lancashire and James Norton.

Viv Hardwick