Grandpa/Grandma is a title unlocked by purchasing the "Farm deeds (+titles)" reward for 250,000 beans in the Farmers' Market. The reward also unlocks the Granny, Potterington, and the Master Farmer titles.
This title changes according to the language of the server on which RuneScape is played, as shown below:
||Großvater [Name] / Großmutter [Name]
||Pépé [Name] / Mamie [Name]
||Vô [Name] / Vó [Name]
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