- Voiced By: Shaun Fleming and later Spencer Fox
- Voiced By: Freddie Prinze Jr. in A Sitch in Time—Future
Kim's brilliant but annoying younger twin brothers, often referred as the tweebs (twin dweebs) by Kim, both are named after their father. Due to their youth at the beginning of the series, they sometimes neglect to consider the consequences of their actions, such as trying to duplicate a version of Adrena Lynn's extreme stunts, which leaves them with significant injuries. Their catch phrase is in the twinspeak language they invented, one saying "Hicka-bicka-boo", followed by the response "Hooo-Sha". When Kim is a senior, the two go to Middleton High school because they skipped grades. They become the Middleton Pep Puppies after Ron joins the football team and can no longer be the mascot. Ron is initially unhappy with this, but accepted it and even gave them a can of mouth foam to use. Additionally, in the fourth season, they no longer dress alike.
Throughout the series, they display a talent for inventing and often use Kim's stuff to create their own inventions. They also help her fix and upgrade the beat-up car their Dad gave her, and program it to increase its speed, endurance, and power. Despite their obvious intellect, Kim has trouble seeing them as anything more than annoying goof-offs, not believing them capable of some of the things they had achieved, such as building a hand-held Silicon Phase Disruptor, believed by Drakken and other scientists to be impossible, or skipping grades to enter Middleton High as freshmen at the age of thirteen. However, there have also been times when Kim showed both true affection and appreciation for them and their skills.