Travel to mexico through us. What do I need to do?

[disconnecteddrifter]

Please could someone help? I'll be travelling to mexico with two children double vaxxed. We will have a transfer in America. I am not sure what I Nedd regarding covid testing. It looks like we will need a test but what kind of test? I'm also not sure whether we need a visa to transfer - there seems to be a reciprocal visa waiver but do I still need an etsa? I don't think children's passports have chips in them?
I'd be really grateful for any advice

Regarding COVID testing, you will need negative COVID tests, even just to transit. All passengers over the age of 2 have to have a negative test. You will need these both ways if you are transiting through the US both ways, .

If you are British citizens you will need ESTA approvals to transit under the VWP (assuming you meet all the usual requirements of the VWP regarding criminal history and previous travel history, etc).

Non-US citizens and non-residents also have to be vaccinated to enter the US, even to transit.

This is as it currently stands. It may change at any moment, of course.

You will need to book a test for everyone at a testing site and have the tests done no more than one day prior to travel, and that is both ways - you will have to do a test at a testing site in the UK, and another one in Mexico, the day before you travel and the day before you return. The test results must be available for airport and airline officials to view. This rule is for everyone over age 2

We went to Mexico via US pre-covid - never again!
We had to buy estas, really annoying as we were only in transit.
Then we had to go through the whole immigration process. Very unpleasant, long-winded & we caught our connection by the skin of our teeth.
We then had to "immigrate" again on the return journey.