He brought the 6-year-old girl to the tent because her eyes were irritated and "she throws up everything she eats".
Several thousand more migrants were trudging along the highway between the city of Puebla and the capital, catching a lift from passing vehicles when possible.
Nashieli Ramirez, ombudsman for the city's human rights commission, said the city was preparing to accommodate as many as 5000 migrants from the lead caravan and several smaller ones hundreds of kilometres behind it, for as long as necessary.
"We have the space in terms of humanitarian help," Ramirez said.
US President Donald Trump has seized on the caravan as an election issue and portrayed it as a major threat, even though such caravans have happened regularly over the years and largely passed unnoticed.
He ordered thousands of troops to the US-Mexico border when the migrants were still hundreds of kilometres to the south, threatened to detain asylum seekers in tents cities and has insinuated without proof that there are criminals or even terrorists in the group.
In dozens of interviews since the caravan set out from Honduras more than three weeks ago, migrants have said they are fleeing rampant poverty and violence. Many are families travelling with small children. Some say they left because they were threatened by gang members or had lost relatives to gang violence; others say they hope to work, secure a good education for their children and send money to support loved ones back home.
Alba Zoleida Gonzalez, 48, from Valle, Honduras, said she had walked for five hours and hitched a ride on a tractor-trailer with about 150 people. Her calf muscles were aching, but that was a small price to pay for the chance at a life better than the one back home.
"I looked for work, and nothing," Gonzalez said, adding that her husband had been robbed and had to hand over everything he made selling crabs so his assailants wouldn't do worse. "And when one does find a little job they kill you for the money," she said.
- AP
