Sue

Sue is an employee of the Gravity Falls History Museum. At the very least, on Pioneer Day.

History
Sue is the one that welcomes visitors by the entrance of the Gravity Falls History Museum. On Pioneer Day she gave Mabel and Dipper a pink and blue balloon, respectively. Later she had to apologize to Deputy Durland with regret as they had just run out of pink balloons.

Appearance
Sue has curly, light brown hair. On Pioneer Day she wore a light blue dress with a slightly darker, sky blue apron and matching bonnet.

Trivia

 * In Headhunters, a "Susie" is listed on the Dipper's Suspects List. Possibly this is her, otherwise this would be the second Susie mentioned in the show so far.