Thank you for all the replies. I prefer to have these issues sorted beforehand, rather than just us 3 turning up at the front desk on the day. I just noticed that on the PH Hamburg page, under room description for all rooms and suites it says "Maximum guests per room: 2 adults and 1 child". Should I take it that this is not valid in reality?
http://hamburg.park.hyatt.com/hyatt/...cale=&start=10