The separation of migrant families in the US was sharply criticised in Europe, with France saying it raised questions about American values -- but EU members are also not above reproach when it comes to child migrants, NGOs say.
The images of distraught children being kept in cages on the US-Mexico border were branded "deeply disturbing" by British Prime Minister Theresa May.
"We don't have the same model of civilisation -- clearly we do not share certain values," French government spokesman Benjamin Griveaux said, describing the images as "shocking".
Yet rights groups say governments on the European side of the Atlantic could do a lot better, particularly when it comes to looking after more than 180,000 unaccompanied minors who have arrived since 2015.
"We haven't seen this kind of cruelty so far," Maria Serrano, senior campaigner on migration at Amnesty International said, referring to the separation of families ordered by President Donald Trump before it was revoked on Wednesday.
"But this is the direction that Europe is taking -- because we have seen families torn apart due to the cruelty of European asylum laws," she told AFP.
Greece, France, Malta and Bulgaria have all been condemned by the European Court of Human Rights for their treatment of migrant families and unaccompanied children in detention in recent years.
And last week the charity Oxfam accused French police of physically abusing and detaining children as young as 12 on the Italian border.
They were also accused of expelling unaccompanied minors to Italy -- which would be illegal under the EU's asylum regulations -- and in some cases, cutting the soles off their shoes to make it harder for them to make their way back to France.
Violaine Husson of French migrant aid group Cimade said her country was not "in a position to lecture" others.
From 41 children in 2013, the number of children detained in mainland France pending deportation with their families rose to 305 in 2017, according to Cimade.
"We are very worried because this practice of detaining children has been normalised in France, and it's dangerous," Husson said.
Spain's interior ministry on its website provides guarantees that migrant parents facing deportation will not be separated from their children.
But NGOs have complained about the overcrowded, unsanitary conditions conditions in the detention centres where they are held together.
- Sleeping on the streets -
The phenomenon of children and teenagers from Africa, the Middle East and South Asia turning up without their parents has been a major source of strain in European countries struggling with their biggest wave of migration since World War II.
Rights groups have criticised the methods used to assess the age of migrants claiming to be underage, with authorities in some countries subjecting them to medical tests.
And there have been concerns over inadequate psychological care for young people fleeing war.
In February, the European Union's own Agency for Fundamental Rights published a report that raised a range of concerns over inadequate efforts to care for these children.
In Italy, where some 700,000 migrants have landed after making the dangerous Mediterranean crossing since 2013, many unaccompanied children have ended up sleeping on the streets or disappearing altogether, the report said.
"Asylum-seeking children in several EU member states had no or limited access to education," it added, while that those living on the streets also risked abuse and rape.
Cases of families being deliberately separated, though rare, are not completely unheard of.
The report raised two cases in Denmark where young siblings were split up when one of them had turned 17.
And there is a wider problem of major delays in reuniting unaccompanied children with relatives elsewhere in Europe, not least youngsters in the Jungle camp in Calais who claimed to have family in Britain.
London has been accused by NGOs of dragging its feet on its promise to take them in.
On Sunday, the leaders of 10 EU countries, including France, Germany, Spain and Italy, will hold talks on resolving the bloc's asylum crisis.
"We are calling on European leaders and governments to fix this broken asylum system," Serrano said.