A doctor can tell if your child has hand-foot-and-mouth disease by the symptoms you describe and by looking at the sores and blisters.
Roast the beets for 50 to 60 minutes. Cook the beets until tender, checking them by inserting a fork into the center of each beet. When the fork glides in easily, the beets are tender enough to remove from the oven.
Peel and chop into cubes golden beets. Toss with vegetable oil and put in a baking sheet or tray, making sure the beets are in a single layer. Add salt and pepper to taste. Roast at 400 degrees F for about 25 minutes, or until beets are soft and have golden brown edges.