I am going to transit at Heathrow next month and am travelling alone with a 3yr old and a 6 month old. I am a little nervous about the transit as I know you can't be given your own pushchair until the luggage belt at your arrival destination. If I can borrow a pram for an hour or so it will make life much easier.
We live in the Middle East and here all the airports have prams you can use, but don't remember seeing them in the UK.