Iorgos "Papouli" Katsopolis (played by Jack Kruschen [1922–2002) is Jesse and Pam's grandfather and Nick's father. He is an elderly Greek man; well, more of a child in an old man's body. Visiting from Greece, he is portrayed as a jolly, friendly man with a failing memory, mistaking each of the girls for their younger sister.
At first, Michelle calls Papouli 'Grandpa', to which he responds by telling her to call him 'Papouli', his reasoning being that 'Grandpa means an old man with grey hair.' Whereas Papouli 'also means an old man with grey hair, but sounds so much better'.
Papouli seems to be a good cook, making dinner for the family before engaging in a 'celebration' with Stephanie, Michelle, and eventually Jesse, which consisted of tossing flour into the air, and yelling "Opa!" (which normally is yelled when celebrating in a similar manner by throwing dishes to the ground, causing them to break).
Papouli begins teaching Michelle 'The Great Dance'. Michelle asks him to come to her school for Share Day and teach her class the dance. He gladly agrees.
Unfortunately, in the early morning hours when Share Day is scheduled, Papouli contracts heart failure and dies in his sleep. When Danny discovers this, he has to break the news to his family. Although upset, everyone seems to understand with his superannuated state this was to be somewhat expected; all but Michelle, who is too young to grasp the concept of death.
When she comes home from her Honeybee meeting and shows off the project she was going to show to Papouli and learns of his death, she throws the project on the floor until it breaks into pieces and storms off in tears. The family does their best to explain what had happened, Danny and Stephanie explain to their loved one how to cope with the loss and control her emotions as best she can, and Jesse offers to go to Share Day with Michelle to do the Great Dance.
Joey and Danny, who had just acquired an unnamed boat, decide to christen their new vessel the "Papouli" in honor of their recently deceased patriarch.
- Gina Katsopolis – wife
- Hermes Katsopolis – father
- Nick Katsopolis – son
- Irene Katsopolis – daughter-in-law
- Jesse Katsopolis – grandson
- Pamela Katsopolis Tanner – granddaughter
- Danny Tanner – grandson-in-law
- Rebecca Katsopolis - granddaughter-in-law
- D.J. Tanner – great-granddaughter
- Stephanie Tanner – great-granddaughter
- Michelle Tanner – great-granddaughter
- Nicky Katsopolis – great-grandson
- Alex Katsopolis – great-grandson
- Stavros – grandson
- Jackson Fuller – great-great-grandson
- Max Fuller – great-great-grandson
- Tommy Fuller, Jr. – great-great-grandson
- Demetri Katsoplolis – grandson
- Melina Katsopolis – great-granddaughter