I have found myself in some of the most desperately sad and frustrating situations in my line of work. None more so than earlier this week standing on the roof of a school on the Lebanon border with Syria watching the sickening sight of shells landing on Homs and Al Quasyr.

Seconds after the strike the smoke billowed and I was left fearing the worst: individuals killed or maimed; families torn apart and left homeless.

But it is not until you speak to the children that the true horror is brought home. Youngsters who have borne witness to atrocities no one should ever see tell of the suffering and brutal reality of the war in Syria.

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Stories like that of 13 year-old Majed who talked about how a machine gun mounted on a tank shot 15 people on the street where he stood. He explained to me how he saw his best friend die on the way to a funeral after he was shot in the back, describing how the bullet came through his tummy and how the hole it left couldn’t be covered with both his hands.

Stories like that of the family of four children I sat with who said their parents had been kidnapped and were still missing. Or the little girl I met who had survived 60 days of bombing - during the fiercest onslaught, her uncle told me, a shell fell on the homes of their friends and neighbours every second.

I’m sorry to say these stories aren’t one-offs. Thousands of children coming across the border have similar tales of anguish, turmoil and hurt none of us can imagine. They speak of snipers on the roof tops of their homes, tanks rolling down streets where they once played and sleeping in the fields to avoid nightly shelling.

The children affected by the war are severely traumatised: they wet their beds, their sleep is broken by nightmares and some have started self-harming. They are desperate, frightened and all too often alone.

Save the Children is doing whatever it takes, both inside Syria and in neighbouring countries, to give children and their families the basics they need to survive. In Iraq, Lebanon, Egypt and Jordan we are helping to support thousands of families - providing food, clothing, shelter and education for children and families who are facing extremely difficult conditions. Our specialist teams are also helping children to overcome their traumatic experiences through emotional support and play therapy.

Along with our partners, we have already reached more than 600,000 people across the region, including 360,000 children. Our teams are working flat out but we cannot scale up our efforts to meet the growing need without additional funding.

The world can do more. We need more aid. We need humanitarian access – cross-border and cross-line. We need a political solution. As horrible as the chemical attacks were - and there can be no doubt they were a crime - the on-going war is killing many, many more.

As a humanitarian agency we don’t take sides. We want to work with all children that need help and we need to see that international law is upheld throughout Syria, on all sides.

Unfortunately, Save the Children often encounters situations where children are dying – through war or natural disaster. But it’s not often we see children targeted. Last week I asked the children I met why they think they’re being targeted. Their answer was truly terrifying: “Because we’re told we are the future.”

Standing on the roof of that school, a hundred metres from the border, it felt like Syria is losing a generation and what’s at stake now is the future of an entire country. We desperately need a way of protecting children.

Our message to the international community is simple: even if you can’t agree on anything else, surely you must agree that Save the Children and other humanitarian agencies must have total access to help those most in need.