Richard and Helen Burch
Like their son, they can only say their own names, they have large heads, and they use wheelchairs. They presumably suffer from the same syndrome that he has. In "Timmy 2000", when Timmy becomes a rock sensation with The Lords of The Underworld, musician Phil Collins goes to extreme lengths to destroy his career under the false claims that he's trying to "protect" Timmy from being made fun of. He attempts to sway Timmy's parents into stopping him from performing, but due to their own disabilities, he finds them unresponsive to his attempts, as they are unable to say anything beyond their own names and flail around randomly. Their family portrait shows the three of them sitting on their wheelchairs in front of the Eiffel Tower. The picture allows us to presume they have some means of consistent income. Their house is green with a gas tank next to it.
Both Richard and Helen have abnormally large heads. They are both confined to wheelchairs due to their disabilities.
Richard has a small tuft of brown hair. He wears a red, button-up coat, white shirt and blue pants.
Helen has long, orange hair. She wears an aqua-green coat, a slightly lighter aqua-green shirt, and a light purple, ankle-length skirt.
Little is known of their personality, as they are unable to speak anything other than their name due to their disabilities. It is assumed their personalities are similar to Timmy's.