Jeff is a character who appeared in seasons 4-6. He is portrayed by Austin Ball.
- His family came from the Philippines. Like Min (played by Pia Hamilton, but credited in all her appearances under Pia Manalo, her maiden name), her family came from the Philippines.
- He lives with his mom, his dad, his older brother - Franco, his baby brother - Leo and his cat - Tiger. His mom, his dad and his older brother - Franco. His cat - Tiger also appeared in A Different Kind of Mystery.
- Jeff's favorite instrument is the clarinet, as revealed in Barney's Band.
- Jeff's favorite season is the summer, as revealed in Four Seasons Day.
- Jeff wants to be a farmer when he grows up, as revealed in Ride with Me.