heathrow to gatwick jet lagged

Here is a link I copied and pasted from another post on this forum. The article has been updated as of May 2024.
https://www.tripsavvy.com/a-guide-from-heathrow-to-gatwick-4126806. That should give you a start. I can tell you we took a private car this past summer from Heathrow to a different location, and it was an absolute life saver after an overnight flight. But depending on how mature your grandson is, the bus may be a great adventure and not be that stressful.

National Express runs a comfortable bus (coach) service between Heathrow and Gatwick. Look at the National Express web site for info on prices etc. Be aware that it runs on two of the busiest motorways in the UK and can hit traffic congestion. Otherwise you need to get into London to take the train. If you are flying on to somewhere else you will need to allow plenty of time to clear immigration, pick up baggage, find way to the bus station. Google Heathrow to Gatwick for lots of info on your options.

I made this transfer using the National Express Bus a few years ago. Probably as easy as anything, minimal luggage schelping.

I'd add my vote for getting the bus from Heathrow to Gatwick.

If there is a major problem on the M25 - the Motorway (Highway) which runs around London - which the bus will travel on about a quarter of, then divert to the trains (check with Google maps when you arrive).

I think the easiest train journey would be Elizabeth line from LHR to Faringdon and then a Thameslink train from there to Gatwick.

The article has been updated as of May 2024.
https://www.tripsavvy.com/a-guide-from-heathrow-to-gatwick-4126806

Easybus no longer operate any of their own airport services in the UK and haven't since before the pandemic. Their website is not awfully clear, in fact somewhat misleading. They are 3rd party resellers for National Express and The Oxford Bus Company 'The Airline' service.

They state that-

easyBus in association with Megabus offer airport transfer bus services between Gatwick Airport, North and South Terminals and Heathrow Airport Terminals 1,2,3 & 5

Well, Heathrow Terminal 1 has been closed for many years now. They offer both Megabus and National Express journeys on their website (not just Megabus). In fact half the so called National Express journeys are really Oxford Bus Company journeys.

Easiest thing is just turn up. Ask at the Information Desk which is the 1st journey out (National Express or The Airline) and buy a ticket for that bus there and then.

Another error on that site: "Note that there are not always busses between 1am and 3pm; check the bus site to confirm." They presumably mean 3am. There is currently a gap as there is no service between 00:40 & 02:45 in the week.