It depends upon which direction the wind is coming from relative to the position of the ship. In other words, if you're heading into the wind, it's not so bad. If it's coming from the side, pax might feel it.
I wouldn't worry about it too much. But, if your daughter becomes sensitive to the motion, I suggest a simple remedy -- apples. They're free, readily available, and have no side effects. They've worked well for me when sailing off the New England coast, where I live. This idea was given to me by a crew member years ago when I was on a particularly rocky cruise and couldn't medicate as I was pregnant.