Considering a cruise for our hols next year, we've never done a cruise before. We have 2 teens and one had been fine on the odd boat trip we've done over the years but recently felt not actually sick but uneasy/vertigo type feeling (that's how they described it) on a boat trip and now doens't want to consider a cruise holiday! My understanding is that you don't feel the waves as such because the ship is just so big. Is that actually the case?