Not far from the Algerian border, the infant gave up its fight for life under the punishing Saharan sun.
"The mother, she is a friend of mine. Her baby passed away in the desert," said Thomas Howard, a painter and decorator from the west African state of Liberia.
Mr Howard and his friend had migrated north to Algeria looking for work but were rounded up, beaten and robbed by Algerian security forces before being put in a truck, driven back south and dumped in the desert.
They were told to start walking south through the dunes as their captors drove away.
Since September 2017, Algeria has left more than 10,000 people at its southern border, leaving them to trek for hours without food or water towards scattered border towns in neighbouring Niger.
North African countries are cracking down on immigration in a bid to stem the flow of sub-Saharan migrants reaching the Mediterranean, and ultimately Europe, and they have received financial backing from Britain and the EU.
As the numbers crossing the Mediterranean fell from 215,997 in the first six months of 2016 to just 40,944 in the same period this year, the amount left adrift in the Sahara by Algeria has jumped.
In May last year, 135 people were left to fend for themselves in the desert between Algeria and Niger alone - according to the International Organisation for Migration (IOM) - but this stood at 2,888 in April this year.
The expulsions happen both during the day, when temperatures can hit 43C, and at night, when migrants fumble blindly in the dunes, looking for shelter and safety.
"Migrants were going to Algeria and at some point they decided they didn't want them there any more," said the head of the IOM's delegation in Niger, Giuseppe Loprete.
The majority of migrants simply want to work in Algeria, say IOM officials. Although some still use it as a route to Europe, only a handful now make it to the boats heading for Italy and Spain.
Better security on Niger's north-eastern border with Libya, following a massive injection of European Union money, has forced people smugglers to reroute towards Algeria.
Algeria receives less of the EU money that has poured into Niger and Libya to deal with border security, but the crackdown is being felt across the region.
The north African state is also suffering an economic crisis and high youth unemployment, and government tolerance of illegal migrants has evaporated, endangering an army of sub-Saharan workers from Cameroon, Guinea, Ivory Coast, Liberia, Mali, Niger, Nigeria and Senegal who were previously tolerated on building sites and as domestic servants.
"Migrants are returned to the border without knowing why, some of them were showing me that they were on a construction site and they are still wearing the clothes they were in," said Mr Loprete.
"Others left behind their savings, and that's why some of them are trying to go back immediately."
Niger implemented a harsh anti-smuggling law in 2015 under pressure from the EU, and will receive €1bn from the bloc by 2020, with specific provisions for dealing with illegal migration.
Several EU bodies operate in Niger, aiming to keep migrants from ever reaching Europe's shores.
© Daily Telegraph