This, a couple of samples from a family shoot I just did, is why you probably want to hire a photographer for a family shoot rather than using an iPhone to just snap away:

Those are pretty much straight from the camera. So what does that take? Well, experience, insight, plus:

1. A large battery-powered flash fired into an umbrella.
2. A couple of pocketwizard radio triggers.
3. Set your shutter to 1/250 sec, ISO to 100.
4. Start at f/8 and be ready to change the aperture to set the background 1-2 stops below nominal (f/11 in this case).
5. Turn the subjects away from the sun.
6. Position them right.
7. Shoot at just the right moment.

Simple once you know. And if you don’t know, I have two pieces of advice: One, learn (I teach, and I write books!) and two, start by hiring a pro.