Nicely exposed family image and will be a good memory aid for you in the future.
A slighly smaller aperture would have helped a bit as I suspect if you enlarge it much more your youngest will look to be a bit soft as focussed on your oldest and at f4.5 doesn't cover a lot of space.
It is a pity about the grass though, and I would probably clone out the gap in the treeline on the LHS