We are travelling with a 4 year old and 6 month old for a city break to London. We will be taking a plane to London and then staying in a flat in central London so lots of buses and trains etc. We have a single pram for the 6 month old and can attach a buggy board for the 4 year old to stand on when his legs are tired. Our friend has lent us a travel double buggy to use if we want. We tried it today and while they both fit in my 4 year old would need to cross his legs so likely not the most comfortable. My concern is that we will need to put the double pram up and down a lot to get on and off transport and through doorways and if the 6 month old is sleeping it will disrupt her. The single we could lie her flat and still have buggy board attached if she wanted to nap. What would you advise? Double or single and buggy board?