Zoe was born with arthrogryposis. A series of operations to her legs and arms have given her enough independence of movement for her to progress to a large academy school where she blossoms and even becomes an enthusiastic netball player. But by the end of her first year one foot is causing her so much pain that a further operation looks necessary. William's condition, tuberous sclerosis, has led to complex epilepsy and autism, which cause him to behave violently and erratically. He is difficult to manage and can show aggression to his devoted mother Paula and younger sister Jess. Paula has also developed MS and, as William gets bigger and stronger, she finds it increasingly hard to cope. She and her husband Nick look into a residential school for William, although she finds the idea of him leaving distressing. Shelbie was born with Trisomy 9-P, a profoundly life-limiting condition. She's be in and out of hospital all her life, and is rushed into Bristol Children's Hospital with an unexplained illness that affects her breathing, and her life hangs in the balance. Hamish was born with achondroplasia (commonly known as 'dwarfism'). Ten years ago his parents moved to the South Island of New Zealand where he has benefitted from great skiing opportunities. Hamish's new passion is swimming. He's been breaking national records and winning medals in the under-19 national championships. His ultimate dream is to swim for New Zealand at the 2016 Paralympics in Rio.