That stat isn't as startling as it seems when you dig in; most of those are custody disputes.
https://www.washingtonpost.com/outlook/most-kidnapped-childr...
> But contrary to the dominant narrative, nearly all child abductions are perpetrated by family members. Stranger abductions — certainly alarming and tragic — actually occur with “lightning-strike rarity,” as a report in the journal Criminal Justice Studies put it, in contrast to the more than 200,000 parental abductions committed each year that meet the criminal criteria and are not merely delayed visitations or misunderstandings.
And the 840k number massively overstates actual active cases; reports can be solved in a matter of minutes/hours, like a lost kid at an amusement park.
https://www.reuters.com/article/factcheck-us-missing/fact-ch...
> Therefore, of the 365,348 missing children (between the age of 0 and 17) reports recorded in 2020, only 30,396 – or about 8% – were still active cases at the end of the year.
(Good luck explaining that to a QAnoner, though.)