Is my ESTA still valid?

If a child is the citizen of a country that is part of the Visa Waiver Program then they will require a valid ESTA to travel to the United States. This applies to children of all ages, including infants, in the exact same way that adults require an ESTA for permission to enter the US.

You can submit a new ESTA application any time you like, even if you currently have an active ESTA authorisation. There are also some circumstances when you will have to submit a new one. Here are a couple of reasons why you would need to submit a new one:

Your ESTA authorisation needs to be valid for when you enter the U.S. and will allow you to stay within U.S. territory for up to 90 days from when you land. Therefore, it is okay if your ESTA does not remain not valid throughout your stay in the United States as long as you do not overstay the limit of 90 days.