Fertilia traveled along the Oregon Trail around 1862, alongside her husband and six children, to presumably settle in the recently founded Gravity Falls, Oregon. She and her husband were later credited for creating the high-five, as Mabel Pines had taught her to do so during her interference with the past.
During Dipper and Mabel's excursions through time in "The Time Traveler's Pig," Fertilia appears with her family on the Oregon Trail, where her husband mistakes the twins as children of hers. Mabel then teaches her how to use a calculator as well as the high-five, as well as revealing women's ability to vote in the future and her light-up sneakers. Believing their actions will have dangerous implications through time, Dipper seizes the Time Machine and sends them back further into the past.
She and her husband Grady are later mentioned in "PinesQuest," where their gravestones credit them for the creation of the high-five.
Fertilia has fair skin and is expecting; she is quite far along in her pregnancy. She has brown hair and freckles. She wears a dull blue bonnet with a dark blue ribbon laced around the middle and a matching dress with a white collar. She also wears ivory socks and brown boots.
- 109. "The Time Traveler's Pig"
- PinesQuest (mentioned)
- "Fertilia" is a pun on the word "fertile," which is appropriate considering she has several children.
- Fertilia and Grady Mecc's last name is an allusion to MECC, the developers of The Oregon Trail video game.
- She is the mother of a record breaking 42 children.