Stayed there many times, the last time being Easter this year. They definately have family rooms for 4 i.e. one king bed and two singles. For some reason they don't appear on the web site but places like ABC Holiday Extras can quote for them.
The only thing is though, we did think the room was looking a bit shabby last trip. Most of the rest of the hotel had been renovated so maybe the family rooms have now. Also the Hilton have closed their pool and leisure facilities (just a small gym there now) so we're going to try somewhere else next time. Still can't beat it for convenience if your'e travelling from South terminal though.