Two tips for today. First, use the light. This was around 6pm. A great time for some soft light if you have a few trees like we do to diffuse the light a bit. I did practically no editing to this photo. This was how the light was.
I personally like the bottom photo best of these two because it is more intimate. I took the first so that in case they stopped what they were doing before I got there that I at least captured the idea. I would have like to have gotten down even more at there level. The idea here, especially with children, catch the moment first and then see if you can better it. If you wait for perfection you may just miss it altogether.