The only source for this number is a terrorist group.
This statistics laundering is happening a lot within the UN.
UN-OCHA's latest report says that "According to UNICEF, 17,000 children in Gaza are currently unaccompanied or separated, constituting one per cent of the total displaced population of 1.7 million people."
The link at UNICEF says, "UNICEF estimates that at least 17,000 children in the Gaza Strip are unaccompanied or separated.....Of course, this is an estimation since it is nearly impossible to gather and verify information under the current security and humanitarian conditions."
So UNICEF made up numbers based on a wild guess of how many children became orphaned or (somehow) separated from their parents, which in turn was based on faked statistics that came directly from...Hamas. But while UNICEF admitted its numbers were an "estimation" and could not be considered accurate at all, OCHA repeats them as official UNICEF stats.
Another UN agency, UNRWA, also repeats Hamas fake statistics.
UNRWA chief Philippe Lazzarini tried to be careful in his wording, tweeting, "Staggering. The number of children reported killed in just over 4 months in #Gaza is higher than the number of children killed in 4 years of wars around the world combined."
But after that weak caveat of admitting that the Gaza numbers are only "reported," he accepts them as proof that Israel is deliberately targeting children: "This war is a war on children. It is a war on their childhood and their future."
It is an antisemitic libel supported and spread by the UN.
WHO also unquestioningly reports the Hamas statistics as authoritative, including the completely made up statistic of over "7,780" people missing or buried under rubble, a number that has only gone up even as fighting has decreased. Has no one been uncovering bodies in northern Gaza for months? When they find a body, does the MoH subtract that from their "under the rubble" figure?
Yet since these statistics are reported by the UN, the media and NGOs feel confident to report them as originating with UN agencies instead of noting that they originally come from Hamas.
It is laundering of statistics.
But the antisemitism doesn't end there. The Hamas statistics are accepted unquestioningly, including the absurd idea that 72% of all Gazans killed are women and children. That would be, as of today, over 22,300 women and children killed.
But Israel says that 13,000 terrorists have been killed. In previous wars, Israel's estimates of terrorists killed have been proven to be accurate.
Presumably all of them are men.
It is impossible for both the Israeli and Hamas statistics to be true, since they would add up to thousands more deaths than even Hamas admits. But the UN assumes Hamas to be accurate and the IDF estimates are not considered.
Believing terrorists over Jews is another type of antisemitism we are seeing constantly during this war.