Peel eight large red potatoes. Put in a pot and cover with water. Add 2 tsp. salt. After water comes to a boil, cook for 20 minutes. Test for doneness with a fork. If they feel soft when you stick fork in, they're ready. If not, boil a few more minutes.
While cooking potatoes, hard boil 4 eggs.
Drain off water and discard. When potatoes are cool, dice them. Add the mayo, mustard, sugar, and celery seed. Cut up the hard boiled eggs and add to mix.
Use the heart of the celery stalk with the leaves still on, and cut up as small as you can. Add 1 cup of that celery to the mix.
Using the rest of the leftover celery stalk cut up and add 1 cup of this celery to the mix (you will be using 1 cup of the diced heart celery and 1 cup of the other diced celery for two cups total).
After everything is on top of potatoes, then stir completely with a spoon. Refrigerate before serving.