One way to keep a four-year-old entertained while you attend to some Important Matters (if it's not raining), is to assign a bit of concrete outside, on which they can create a beautiful display. Using only things from the garden. As long as they don't pick the prize-winning roses. Not that I have any of those.
This embroidery from the other day became a child's linen foraging satchel, and then I made a few for my shop update today as well. Lots of room inside for all the things you just can't leave on the ground: acorns, hazelnuts, leaves, strawberry blossom, feathers and pegs of course.