It's a big year for the Radford family, the UK's biggest family living under one roof. Mum Sue is awaiting the arrival of her 16th baby, and her eldest daughter Sophie, who's 18, is following in her footsteps and expecting her first baby the month before. With a planned road trip to France, Sophie and boyfriend Joe becoming first-time parents, and Sue and Noel becoming grandparents... And all this while Sue has to keep up with nine loads of laundry a day and Noel works hard to feed 18 hungry mouths.

How do large families manage to discipline and educate their many offspring, while continuing to add to their numbers? In the Salim's Rochdale home, ex-teacher Mohammed wants to instil a love of education in his children. But with no routine, homework often done late at night and non-existent bedtimes, the kids rule the roost, while Mohammed tries to persuade his wife Noreen to have another baby. In Kent, the Sullivan family take a very different approach to discipline. Tanya and Mike home-school many of their 11 children and believe routine creates order. They want to protect their large brood from the negative aspects of society and dream of one day moving their supersized family to a remote part of Ireland.

How do the mums of large families keep on top of it all? And how do they cope when the kids grow up and start moving on? This episode meets two mums at different life stages who are keeping it in the family. Tania Sullivan has her work cut out when she brings home her 12th baby, but the 37-year-old still manages to set the wheels in motion of pursuing her dream of a self-sufficient farming life. Tracey Lewis has 13 children, some of whom are starting to move on and move out. Tracey has always had a close bond with her beauty pageant-loving daughters, but now that her only son Charles is set to leave home, she is left to face the fact that she's losing her boy. Aged 49, Tracey can't have any more children, but with Charles' girlfriend pregnant and Tracey's own daughter Chantelle also expecting, the dream of a big family continues through to the next generation.

How do dads cope with a supersized family? In Bournemouth, Pete has 12 daughters and dreams of quality time with his wife, while Gary Freer has quit work to help care for his large brood. Pete Lewis's only son Charles has recently moved out, leaving this dad of 12 daughters the only male in a very pink-themed house. Mechanic Pete finds that getting his wife Tracey to stop focusing on their expanding family isn't easy. When disaster strikes over Christmas, Dad is needed more than ever. In Ramsgate, Kent, Gary Freer has given up his job as a long distance lorry driver to help his wife Kirsty care for their supersized brood. Two of the couple's nine children need extra care: 15-year-old Jordan has ADHD and is home-schooled, while seven-year-old Paul is in and out of hospital with a medical condition affecting his oesophagus. When Paul's operation is delayed until after Christmas, their son's health threatens to overshadow the festivities.

In this episode, the parents of two supersized broods struggle to decide when to jump off the baby making roller coaster. In Sunderland, mum of 11 Amanda Allan is losing weight and enjoying getting her life back on track so much she wonders if enough is enough. But her husband Tony, a pigeon breeder, wants one more. Meanwhile in Dundee, Mormons Roy and Emma Hann are both keen to expand their 12-strong brood. But with 43-year-old Emma still breastfeeding 19-month-old Posy several times each night she's exhausted and it's taking her longer than usual to conceive.

Sibling rivalry threatens harmonious family life as the parents of two supersized broods make wedding plans. Britain's biggest family, the Radfords (who number 16), decide to renew their vows 20 years after their first wedding. Their dream is a ceremony on the beach, but with their army of kids being the bridesmaids and pageboys, will their demands put a strain on the usual Radford peace? Roy and Emma Hann's eldest daughter Rachel is set to be the first of their 12 children to tie the knot in a Mormon church wedding in Dundee.