A week after five people died off the Coast of France as they tried to cross the channel in an overcrowded small boat, we have managed to piece together what happened to the youngest victim, who was just seven years old. Sarah was visible as she was carried on her father's shoulders as the police chased them across the beach. Our correspondent, Andrew Harding, who witnessed what happened that night, has tracked down the little girl's father. He described what happened and why the family took such a risk on what was their fourth attempt at crossing.

This was the scene last week, as smugglers clashed with police on a French beach. And in the middle of the chaos, one unforgettable image of a small girl perch pushed on her father's shoulders, a seven-year-old girl with moments left to live. We now know her name was Sarah, and this is her story. Sarah was born in Belgium but grew up in Sweden, one of three children. Here they are with their father, Ahmed. He'd fled from Iraq in 2009 and spent years trying but failing to get permission to settle anywhere in Europe. He got married, worked, had children, but his asylum appeals were rejected. Instead, he says, the whole family faced deportation to Iraq, which is why Ahmed brought them here instead. Hiding with smugglers in these dunes near Calais. So you were with your whole family here, all five of you?

With family, with everybody. And family stay. See it for this side.

Ahmed brought us back to the French Coast to explain what had happened and why he put his family in such danger. He shows me how they rushed towards the sea.

And you're racing now? Yes. You're trying to get to the water before the police? Yes. It must have been scary for the children.

Yeah.

The police caught up with them near the water's edge. We were there, too, filming the whole incident, the smugglers fighting back. And then here on the right, Sarah, in a pink jacket, making her way towards the boat, still holding her father's hand. A little later, you can see her on Ahmed's shoulders. Then she disappears into the wildly overcrowded boat. A rival group of smugglers had directed their passengers from Sudan towards the same boat. As more migrants piled on board, you can hear Ahmed shouting for help.

She said, Help me, dad. But I couldn't reach her. There were people standing on top of us, and Sarah disappeared below me. I was trapped. I told one man to move. I screamed and hit him, but he just looked away.

Asure, the French police made no further attempt to intervene. It was only later, at sea, that a rescue boat finally took people away to to reveal Sarah's dead body.

Finally, when the rescue boat came, they started to pull people out, to pull out the dead. Then I saw Sarah. She was in the corner. Her face was blue. She wasn't breathing.

There will be people watching this who will say, Why did you take that risk? Why were you prepared to take such a risk for you and your family to try to get to England? How do you explain that?

The sea was my last option.

I applied 14 times for asylum, but they were all denied. I went to Belgium, to Sweden, to Finland. I didn't want any handouts. My wife and I can both work. All I wanted was for my kids to go to school, to have dignity.

Before she left Sweden, Sarah drew through this family portrait. That's her on the right. Today, her old school teacher said the class was mourning her death. She was a nice girl with lots of friends at school.

When we heard she died, we gathered in a circle and had a minute's silence. They were such a nice family. I was really shocked to learn they were being deported.

Sarah and her siblings had only ever lived in Europe. Her funeral is expected in the coming days. For her father, there is grief and guilt and still no clarity about which country he and his broken family can ever call home.

For now, the family looks set to remain here in Calais, where as summer approaches, the weather improves. French police are bracing a big surge in the number of attempted migrant crossings. And of course, we're all waiting to see whether the new British policy of deporting people on flights to Rwanda will have any deterrent effect on those getting into these small boats to make this dangerous journey to the UK.