A study from De Montfort University and the University of Ulster found that people with sisters tend to be happier and have better mental health. Researchers surveyed 570 people aged 17 to 25 and discovered that those with sisters were more likely to openly express their emotions, leading to a more positive outlook on life. Noni Radebe, who stands in for Leigh-Anne Williams, chats to Sandra Rosenberg and Delucia Daniels about what it means to be a sister and the best lesson they have taught them.