It could also explain to parents that they should take an interest in their child’s education, go along to parents evenings and encourage them to do their homework.While there are public information campaigns aimed at parents of infants, ministers have been reticent about doing the same for those responsible for adolescents, Dr Homden said.“There was, rightly, a great deal of emphasis on learning readiness for school and there is a focus at the moment by government on speech and language acquisition,” she said.But concern about the perceptions of the “long arm of the state” has held the Government back from taking a more proactive stance on advice for parenting teenagers.Ministers will launch a public information campaign later this year urging parents to “Chat, Play, Read” with their children before they start school.The Education Secretary has promised to tackle the “last taboo” in education by highlighting the fact that many mothers and fathers are failing to teach their children how to talk. “What the red books says is what is supposed to be happening for our child at that point.“Are they supposed to be sitting up and smiling? Am I supposed to be taking them for a hearing test? Are they supposed to be having an MMR jab? If your child doesn’t crawl within a certain [time frame], you would go and get help. Where is the equivalent for parents to understand the developmental curve for our child in adolescence?”Parents are given a Personal Child Health Record – known as the “red book” – when their child is born, which serves as a manual for their baby’s development.Dr Homden, who was awarded a CBE in 2013 for services to children and families, said that parents of teenagers need guidance so they know when to intervene and when to seek help over their child’s behaviour.“We would have parents saying to us is it normal for my adolescent to never come out of their bedroom and to behave in these ways? When do I need to be concerned? This is parents who are on the case,” she said.A red book for teenagers could include advice on how much sleep adolescents need, as well as the importance of setting routines, structures and boundaries, Dr Homden explained. The Government should introduce a “red book” for parents of teenagers to stem the tide of knife crime and gangs, the head of the UK’s oldest children’s charity has said.Many parents are ill-equipped to deal with the challenges of adolescence and do not understand the importance of setting rules and boundaries, according to Dr Carol Homden, chief executive of Coram.Teenagers are more vulnerable to being groomed by gangs if they come from unstable home environments and are left “searching for attention and belonging”, Dr Homden said.Earlier this month, the Home Secretary announced a series of new measures designed to crack down on violent crime. Under a statutory “public health duty”, police, hospitals, schools and other public bodies would be required to report those at risk of being drawn into knife crime.Staff would have to alert other agencies if they thought a young person was in danger – such as turning up at A&E with a suspicious injury, absenteeism or worrying behaviour at school or problems at home.But as well as empowering various public agencies to combat knife crime, ministers should also give better guidance and advice for parents, Dr Homden said.”As a parent, we all love our red book for infants,” she told The Telegraph. Want the best of The Telegraph direct to your email and WhatsApp? Sign up to our free twice-daily Front Page newsletter and new audio briefings.