Early childhood development became a global campaigning issue in 2016 - here we look at some of the key research, achievements and challenges in the push to give every young girl and boy the nurturing care they need.
Early childhood development isn't a new concept. But 2016 was the year when a global movement began to grow - a movement demanding that all children get the nurturing care they need.
It's important for all young children that they have access to health, nutrition, play, learning and protection. But in the developing world in particular it can be the vital element that sees a child stay in education and fulfil their potential into adult life.
As we count down towards the end of 2016, we look at some of the achievements, challenges and reports from this year and the issues facing early childhood development in the poorest countries in 2017.
The #5for5 campaign
Theirworld launched the ground-breaking #5for5 global campaign about the importance of early childhood development - highlighting that these tender years are crucial and will map out the rest of a child’s life. They are so important they can even impact on a developing country’s economy.
By the time a child reaches five years old, 90% of their brain has already developed – which means the progression from birth to school is the most important time of their lives.
#5for5 aims to raise awareness of early childhood development and put pressure on world leaders to take urgent action to make sure all young children have access to the care they need, including nutrition, health, learning, play and protection.
5 seconds. 5 steps. 5 goals. It’s all #5for5.
The Education Commission
A group of world leaders and experts spent a year researching and analysing the state of global education and delivered a major report called The Learning Generation to the United Nations in September.
The Education Commission warned hundreds of millions of children around the world will be robbed of their future unless immediate action is taken. It said every child should have two years of free, quality pre-school education.
At the report launch in New York, UNICEF Chief Executive Anthony Lake said: "Investing from the earliest days of a child’s life is critical to the development of the brain. It is a once in a lifetime chance to build the future of a child - no stage in a child’s life is more important."
In the world’s high-income countries, 87% of children go to preschool. But in low-income countries it is only 23%. The commission said its Learning Generation pathway - a radical plan to give every child the same education opportunities - will see those numbers jump to 89% by 2030 and 99% by 2040.
Why the first 1000 days are so crucial
Properly-funded policies and programmes during the first 1000 days of a child's life could help 250 million at-risk girls and boys.
Those crucial days are when a child most needs development care including early learning, health, nutrition, play and security. Yet many children are exposed to poor sanitation, infections, lack of nurturing care and inadequate stimulation during this period, said the findings from The Lancet's Series on Early Childhood Development.
“Increasing numbers of children are surviving - but begin life at a disadvantage because they do not receive the nurturing care they need," said series author Professor Linda Richter of South Africa's University of the Witwatersrand.
"Political prioritisation, legislation and financing of early childhood development programmes are key to ensuring their success, as is creating a policy environment that supports nurturing care."
Millions will miss out warns UNICEF
A lack of early childhood development will deprive hundreds of millions of children the chance to fulfil their potential, UNICEF warned.
The vast numbers of children missing out on learning in their early years is hugely concerning, said the UN children’s agency in its annual State of the World’s Children report.
Executive Director Anthony Lake said: "Denying hundreds of millions of children a fair chance in life does more than threaten their futures - by fuelling intergenerational cycles of disadvantage, it imperils the future of their societies.
“We have a choice - invest in these children now or allow our world to become still more unequal and divided.”
Snapshot of millions being left behind
In many of the poorest parts of the world, huge numbers of girls and boys are being "left behind" because of factors like malnutrition and inadequate childcare in their early years.
The findings for 53 countries across Africa were revealed in a snapshot produced by Theirworld that looked at equity and early childhood development on the continent.
The report said: "The data tells a very clear story - millions of children are being left behind at every developmental milestone and those left behind are disproportionately poor."
Brain tests can predict future for three-year-olds
At the age of three, brain tests seem to predict a child's future chance of success in life, according to researchers.
Low scores in cognitive tests for skills such as language indicate less developed brains, they said. This could be the result of too little stimulation in early life and these children are more likely to become criminals or be dependent on welfare or chronically ill unless they are given support later on.
The New Zealand study appeared in the journal Nature Human Behaviour. Professor Terrie Moffitt, from Duke University in North Carolina, who co-led the study, told BBC News: "The earlier children receive support the better.
"That is because if a child is sent off on the wrong foot at three and not ready for school they fall further and further behind in a snowball effect that makes them unprepared for adult life".
Kenyan report shows more action is needed
A report by Theirworld and the Kenyan organisation KANCO said almost 40% of Kenyan children aged three and four are not reaching their developmental milestones.
Kenya has made progress over the past 15 years in improving access to early years care - but more action is needed to ensure every child has the best start in life.
Without it, children from the poorest and most marginalised groups will continue to be left behind their peers and unable to fulfil their potential at work and in the community.
Allan Ragi, Executive Director, KANCO, said: “We need to start with the youngest children, starting right from birth and ensure they receive not only adequate nutrition and health care services but also essential care, pre-primary education, protection and mental stimulation.”
A report from Theirworld and KANCO says Kenya has made progress over the past 15 years in improving access to early years care - but more action is needed to ensure every child has the best start in life.