Cute family pic :-) The colors are brought out well by the sunlight here. It's a pity this side of the foal is in shadows but you couldn't have done too much more about it besides moving your position, but then you may not have been able to get such a good image.
Unfortunately, they are in the shadows and it's hard to see the animals, especially the little guy. Judging from the placement of the shadow of the mom, it looks like it's high noon...perhaps waiting just a little later in the day would have helped.