OK I love TripAdvisor and use it all the time for flights and hotel bookings.
Today however I decided to start getting prices for my family vacation to the United Kingdom (LHR), flying round trip from Philippines (MNL). I input my dates 24th March 2012 to 29th April 2012 and number of travelers 5.
Unable to locate anywhere to state whether adults or children, so just entered 5 travelers.
Results came back stating Kuwait Airlines were the cheapest. I clicked on select this flight to see what the total would be and was directed to the CheapOair website.
At the CheapOair website it showed that we were a party of 5 adults. OK no problem, I'll just redo my booking using CheapOair as I am able to input the number of adults and children.
To my surprise when I did this the fare came back $200+ cheaper than what the quote from TripAdvisor was for the exact same flight.
Kuwait Airlines offer a child discount which basically equates to me getting almost free travel insurance for the 5 of us if I opt for it.
I still love TripAdvisor and will continue using it. I just wish to point out that if you are travelling with children, you may want to do what I did and see if the airline you have chosen offers child discounts. I don't think many do, but Kuwait Airlines do :)