(please, anyone who knows more then me, please correct me)
I am new to all this, but I am a techie, and love reading anything I can get my hands on, so here is some book smart advise (with little to know real work experience)
the 50mm 1.8 wide open is going to let a lot of light in. This means one of two things will happen with the other two parts of the equation (shutter speed and ISO)
You will have lower ISO, and a long shutter speed
You will have higher ISO and a fast shutter speed
If you plan to hold the camera, and want sharp images, you will need to up the shutter speed. This means the ISO will go up, and as it goes up, you get more noise.
If you have a good enough sensor, you can take high iso shots and they will still look good, but really at 1.8, your most likely going to want to steady the camera on a tripod (or something other then handheld).
Also wide open, you end up with an extremely shallow focal range. Gives you that great look, but is harder with moving objects.
If you want better looking photos, you can experiment with a tripod in the living room with the kids playing (if that's a piece of equipment you want to take on your trip), or just step down the camera to f2.8/3.5 or something, and sacrifice the DoF.