It is not the bandage around his head that tells you something terrible has happened to five-year-old Mohammed.
It is his expression and the way he behaves. No smiles, he does not even speak but fixes you with a mournful, unyielding gaze.
Beside him his father, Khalid Yunis, fidgets with his worry beads.
Khalid Yunis calls the US Marines who wounded his son 'criminals'
They are the only survivors of 16 members of the same Nasiriya family, killed - they say - by US Marines who opened fire on the truck in which they were travelling.
This is one of many tragedies in this southern city, scene of the bloodiest fighting of the war.
According to doctors and human rights groups, at least 1,000 people died here - the majority civilians - as the marines clashed with Iraqi soldiers.
Nasiriya's main hospital recorded more than 600 deaths directly related to the fighting and treated over 3,000 people for injuries.
Iraqi troops were among them, says hospital director Dr Kamal Ali. But, he adds, "most of them were civilians".
Across a city of 350,000 residents, the death toll could be twice that, Dr Ali said. Other smaller hospitals were similarly inundated with casualties.
Many of those killed would have been quickly buried, in accordance with Muslim tradition.
I saw many dead and injured civilians myself at the time, including in the main hospital.
An Iraqi group called the Campaign for Innocent Victims in Conflict (Civic), which is trying to compile a total for the entire country, has come up with similar estimates.
Its researchers believe 1,117 people died in Nasiriya as a result of the fighting, the vast majority civilians.
This compares with an Associated Press estimate of 1,896 civilian deaths in Baghdad - a city some 14 times larger - and 3,240 for Iraq as a whole.
Khalid Yunis says he cannot bear to speak about what happened to his 14 relatives. It is his nephew Muaid, who tells their story.
He shows me photographs of their burnt, bullet-ridden truck.
It was late March, on the third day of fighting in Nasiriya, Muaid explains. "They were trying to escape the city, to somewhere safer. I stayed behind."
[The children] made themselves combatants"
Sergeant Michael Sachim-Smith
But as they approached a marine checkpoint on the north side of the city, he says, they came under fire.
The Yunis family tried to make it clear to the marines they were unarmed civilians, Muaid says, but they kept firing.
He says he hates the Americans now. "I consider them criminals."
Marine commanders do not dispute that innocent civilians were killed in Nasiriya.
But they say the unconventional, guerrilla-style tactics used by the Fedayeen - including the use of civilians as shields - made such casualties inevitable.
"They would store weapons and fight out of hospitals and schools," says Colonel Ron Johnson, of the marine unit sent to Nasiriya.
Such tactics were "against the rules of war". But, he adds, the use of precision weapons minimised the civilian toll.
The battle for Nasiriyah raged for 11 days
The most bitter clashes were along a main road between two key bridges through eastern Nasiriya - a road that became known as "Ambush Alley". Eighteen marines died there on the first day of fighting.
Sergeant Michael Sachim-Smith says that in some cases his unit came under fire from "kids who looked around 10 or even younger".
They had no choice but to return fire, he says: "they (the children) made themselves combatants".
By the time the city was finally in US hands more than 30 American troops had been killed and over 60 injured.
The majority of the casualties were marines, but some were soldiers from an army support unit that took a wrong turn into the city and fell into an ambush.
Six were taken prisoner, among them Private Jessica Lynch.
It took some effort to find former members of the Fedayeen willing to speak, hardly surprising with US troops still patrolling the city.
Barzan admitted his unit used schools and hospitals as cover, but said it was fear of the regime rather than loyalty that kept the Fedayeen fighting.
"The government was still in Baghdad. We were all frightened, it was still Baghdad, Baghdad, Saddam, Saddam."
Yet despite the heavy fighting, Nasiriya is starting to get back on its feet - certainly far more so than Baghdad.
Water supplies are still patchy, but the electricity is on most of the time. The marines now in charge of the city have appointed a local Iraqi council and they are running joint US-Iraq police patrols.
But Shia groups have also played a key role, organising street clean-ups, providing security and helping schools, hospitals and other institutions to start functioning again.
But back at the hospital, there is no condemnation or bitterness from Dr Kamal Ali for the high death toll in Nasiriya.
It was worth it, he claimed, to get rid of Saddam. "This is the least price, the cheapest price. That is because there was daily killing and daily suffering under the previous regime."
Even Muaid Yunis, mourning his 14 relatives, admits he is glad Saddam Hussein's regime is finished.
Andrew North presents: 'Nasiriyah: Battle for the Bridges' on the 'Assignment' programme on BBC World Service from Wednesday 18th June and on BBC Radio 4 on Thursday 19th June 8.00pm