Gaston Simpson was the son of Howland Simpson and Gabby Crouse and the half-brother of "Old Tut" Simpson, Lou Simpson, Hugo Simpson I and the full-brother of Dulcine Simpson. He seems to have been a clown and slightly resembles Krusty the Clown. He is Abe's great uncle and great-great uncle to Homer Simpson and great-great-great uncle to Bart, Lisa and Maggie. He was most likely born in the 'Old Country', which seems to be Ireland or Scotland.
- He is addressed to as the half-brother of Hugo, Old Tut, and Lou and the full sister of Dulcine by other wiki pages. This could imply that the Simpson Family Tree's canonicity on Gaston and Dulcine's parts are questionable, meaning that they are the two real children of Howland Simpson.