One of the hardest things to do is to take a great picture of your kids. I have a few tips to make that easier: 1. Pick their best time of day for pictures whether you or hiring someone or taking them yourself. I find that for most kids that is morning.
2. Make sure your kids are well fed. Also bring snacks, drinks, and treats to make things easier.
3. Play and interact while you are taking their pictures, it brings out the bright side of their personality.
4. If they are having a tough time, give them some time to reset. Whether I am taking pictures for other people or myself I find that this comes in handy to change the mood. I am more worried about getting the right shot than about the time on the clock.
Happy Shooting!