Harriet Biggle is the mother of Bradley Biggle and Henrietta Biggle. She made brief appearances in "Raisins" and "Coon vs. Coon & Friends". In both occasions, she walks in on Henrietta in her room, for which she both praises Henrietta and suggests she should spend more time with her sibling.
Harriet is usually optimistic, with a cheerful voice, even when Henrietta insults her and calls her names. In "Goth Kids 3: Dawn of the Posers", when her husband told her to be 'firm and direct', she responded to her daughter with, 'How's my little sunshine?"
She appears to ignore Henrietta's insults; but still loves her very much. She is always concerned about her daughter's behaviour, and even sending her to an 'Emo Camp'. However, she doesn't really know how to properly respond firmly to Henrietta, and when she got dissed by her, she simply responded 'fatty.'
The episode "Dead Kids" reveals her first name; she and Linda Stotch had led Sharon to the Elementary entrance hall so that Randy could serenade his wife, much to her anger as she berated Harriet and the others for not seeing the issue in constant school shootings.
Harriet wears a yellow button-up shirt under an orange sweater and a dark blue skirt. She also wears pink earrings and black shoes. She has wavy brown hair, brown eyebrows, and red lipstick.
Bradley is her adopted son. She appears to care for him very much as she suggests to Henrietta that she should allow Bradley to play with her.
Henrietta is her biological daughter. She appears to be in denial to Henrietta's rude attitude and her extreme dislike for her own mother. In spite of this, she loves her daughter very much and praises her creativity.