Father's Day

Father's Day is a special day of observance for fathers, that is usually held on the third Sunday of June on modern-day calendars.

Mainstream Smurfs Media
In the Smurfs cartoon show, it is known as Papa's Day, and it is celebrated by the Smurfs to honor Papa Smurf in his role as their father figure. In the episode "A Gift For Papa's Day", the Smurfs give him a special hat created by Tailor that Papa Smurf doesn't particularly like wearing, and ends up spending most of the episode trying to discreetly get rid of.

Empath: The Luckiest Smurf stories
In the EMPATH: The Luckiest Smurf story series, it is known as Papa's Day by the Smurfs, which has been used to honor the fathers in the village up until the time of The Plague, after which until Empath became a father himself it has been used to honor Papa Smurf in his role as the Smurfs' father figure. In the village on Smurfette Island, the Smurfettes use this day to honor Father Time in his role as the guardian of time, who occasionally visits the island.