Bill Lorenz of the International Organisation for Migration (IOM) is keeping a diary for the BBC News website as he helps thousands of Sudanese trek home to Raga in the south-west, following a deal to end a 21-year war.
He is transporting the most vulnerable on trucks through forests and swamps in a race against time, as the heavy rains are due.
Wednesday 27 July
We are worried about Shefron, a 13-year-old boy with a ruptured appendix.
We can't operate on him here in the bush. The only thing Aden, the IOM doctor, has been able to do since Monday night when it happened, is to put Shefron on antibiotics and feed and hydrate him intravenously.
Aden tells me Shefron is a little better today but he is constantly monitoring him.
There have been a few medical emergencies and tragedies in the past few days that have left us all feeling low, particularly Aden.
He tried to organise a medical evacuation of Akello, a 17-year-old girl, who needed a caesarean.
But nobody could evacuate her. To save her life, Aden had to cut the front joint of her pelvis to get the baby out.
It was dead, but at least Akello survived. We thought we were going to lose both mother and baby.
Two children have also died. A nine-month-old baby of an infection after her canine teeth were pulled out in accordance with tradition.
The mother is distraught and unable to do anything. This is the third baby she has lost from various illnesses. The grandmother is fetching water, cooking and taking care of the father, crippled by polio.
The other death was that of a two-year-old girl. She had had diarrhoea and pneumonia on and off and had become severely malnourished. She developed an infection and died during the night.
Neither of the families had brought their children to see Aden and it frustrates him.
The emergencies and illnesses of the past few days would have been easily managed in a hospital.
Aden knows that in rural Africa where often there are no health facilities, what he is experiencing now is a daily reality for the people there.
The medical emergencies have been taking up most of his time. It's just as well there have been few people coming to the clinic.
Since the food air drop, which finally happened on Sunday, people have been too busy pounding maize.
The food drop was very successful. Normally a lot of food bags break open in a drop. But this time, there was little damage - and a lot more grain to pound.
Some people have begun to leave this camp at Rede, but we expect a large group to leave tomorrow when they've finished making flour.
People are tired. But there is real excitement among them.
The cutting teams are now 34km ahead of us. They are hoping to get to Deim Zubeir tomorrow night.
It's the only piece of good news I feel I've heard in a while.
Nevertheless, I am concerned where people are going to camp once they get to Deim Zubeir.
We thought it had been decided they would live in a place called Bile near Deim Zubeir. They would live alongside the people of the town, still under the control of Sudanese government forces, but not with them.
But it now seems others think the two groups should live together.
It's not what this group wants, nor the authorities in Deim Zubeir.
There will be more talks this weekend to sort this out, but it's leaving it a bit late. People will have begun arriving by then.
My other headache is the trucks. There are fewer and fewer trucks able to do what they are supposed to.
Emmanuel, a northern Sudanese businessman, is going to Fala Walla to try and repair a 15-ton truck that broke down weeks ago.
If he can't, our other 15-ton truck will have to tow it.
Another truck stalled going up a hill near Yakap today and won't start.
We'll have to use a precious working truck to push start it. But if things work out, by tomorrow we'll have all of them working and carrying people forward.
We are all going to pray hard tonight.
Below, Bill answers some questions sent in by BBC News website readers.
Yonas Ghidey in Eritrea asks: I would like to set up a business in south Sudan,
particularly in Juba. As an eye witness in the area, what would you
advise me to take into consideration?
I would advise you of the lack of infrastructure in southern Sudan, of the need for people to be involved in transportation.
In fact, there is a need for all services, transportation, education, materials etc.
The other thing is to find out where your ethnic community is located. Juba will become the capital of southern Sudan, but only in about two and half years.
Marko Tito Tibo in Canada wants to know if the IOM has any other missions to help displaced southerners to return home and whether it will carry on the good to assist others in different parts
of the country to return to homes safely.
No, this isn't the only mission. We will be working with the United Nations and other agencies to help hundreds of thousands of south Sudanese as they head home.
There will be way stations where people can get essential services and shelter. We will also provide emergency transport to stranded and distressed vulnerable people as they return home.
However, we lack the funds to do this. We need about $21m to carry out this programme for the very many people wanting to or are planning to go back home and although we have appealed for this, we have received very, very little.
Baak J Yout in the US asks: Being Sudanese I know how hard it is to get clean water - so how have you been getting drinking water on your trek?
We have been using river and pond water, boiling it and then chlorinating it before using it.
Until now, we have been using river water as it is running water. But there are no more rivers now on our journey so we are having to use pond water.
Luckily for us, we are in the rainy season so the pond water is not as dirty as it could be. Otherwise, water would really be a problem.
Kuek Garang in the US asks: What is the new government doing to help you to get this population back home, and what are they doing to prepare for their arrival?
The new government is in the process of being formed and there is a period of time during which this formation takes place.
So it is not really a question of whether the new government has been helping us but rather have both parties been helping us in southern Sudan? The answer is yes.
A thing to bear in mind is that some of the people on this journey are part of that new government/administration for the south. And they have been very helpful to us in this operation.
Since this new administration in the south also does not have resources or employ people yet to work for it, it is depending on UN and other agencies to help their people.
But it helps them to help by facilitating wherever it can. The UN, non-governmental organisations and others, including the Sudanese government's Sudan Relief and Rehabilitation Commission, are also co-ordinating assistance for these people for when they arrive.
Akeri M Isara, a Sudanese reader living in Beirut, asks: Can you let me know any news about my village between Nimule and Opari?
I am sorry, but we have not passed any villages since we left Tambura so I can't give you the news you want.
Ahmed Qasm in Saudi Arabia says: Please inform us about the danger of mines. Are there any serious steps regarding mine removals?
The danger of mines arises closer to Deim Zubeir since it is a garrison town.
As far as I know, there are no plans for demining in this part.
That is why these people are building a road through forest in order to avoid the old trail to Deim Zubeir which had been mined.
I am not aware of the plans of the demining organisations so I can't be more specific on what is going to happen elsewhere in southern Sudan.
Kipruto in Kenya asks: Are there people travelling with you who might not find their families when they get to Deim Zubeir? What will happen to them? And is there hope for the children and young people of Sudan? Will they go back to school? What will happen to them?
My impression is that most people know where there families are. Some of them might find that their spouse has remarried after so long. I know of a few cases where the women who stayed behind, did get remarried. But in general, people know what has happened to their immediate families. They are prepared for whatever their new family situation may be.
Children and young people are a priority for group. They want to open a school when they get to Bile/Deim Zubeir. The UN has plans to open a school. There are 13 teachers among the group. Everyone recognises education is a priority which is why they ran a school in their camp at Mabia where they lived for four years.
F Muller in the US asks: Does the group have any specific religious beliefs?
The majority of the 5,000 people are Christians. However, there are also some Muslims and some Pagans among them.
Delor Adams in the US asks: I would like to volunteer for a teacher-health position. How do I go about doing this?
I am sure that NGOs will be working on education programmes in southern Sudan if they aren't already.
Organisations such as World Vision, Care, CRS (Catholic Relief Services) are among those who would probably be involved in such activities. Maybe it is worth looking on their websites to see if there are any openings.
However, bear in mind that education will be in Arabic. The people in south Sudan are, however, very interested in establishing English programmes for their children.
Kok Bol Bulabek in the UK asks: Why did you not use the route which are been used by
SPLM from Western Equatoria to Bar El-Ghazal that's through Rumbek,
Tonj, Gogrial, Malual Kon and to Aweil West and there to Raja? I believe
this route is safe and secure and is being used by NGOs, instead of
this long way you are using at the moment. It could have been
faster using this route by trucks.
A group went from Tambura to Wau to Raja before this one. It had to cross 100km of mined roads so it wouldn't have been viable for trucks to take this route.
In any case, IOM didn't select the route for this journey or plan it. The people in this group decided for themselves. We joined three weeks later because there was an obvious humanitarian need to help those who were old or vulnerable en route.
Also, the route you suggest would have involved a much greater distance. People would not have been able to walk for that long. Their leaders picked the shortest, if most complicated, route possible.
Mading Ngor Akec Kuai in Canada asks: With the presence of the LRA [Ugandan rebels] and the pro-government militia in south Sudan, how secure are the returnees? Notwithstanding that, there is a shortage of food supplies and the international community needs to step up efforts to accelerate the peace process and assist the incoming Sudanese back to their homes.
There have been no problems with the LRA or militia. We have had problems with two groups of poachers, who had turned to poaching after their militias had been disbanded.
With regard to your second point, the place where the group is heading, Bile, is an agriculturally rich area. There are few people there and there are good water supplies. They will be able to produce enough food there, as long as they get the help in starting up such as seeds, tools and food supplies until they can harvest their crops.
In terms of assisting those that have yet to make the journey home, yes, you are right. Resources have to be put in place quickly to help the hundreds of thousands of people expected to return to their homes. Returns in large numbers are likely to begin in the coming months after the rainy season.
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