HOUSTON—With the challenges accompanying his developmental disorder widening the already vast gulf between his parents, autistic child Evan Thomas, 3, continued this week to destroy the failing marriage he was brought into this world to save.

The Thomas family in 2007.

Evan, who through the very act of being born was entrusted with the task of resolving lingering conflicts, soothing deep-seated contempt, and restoring intimacy to Mark and Sharon Thomas' long-strained relationship, has thus far utterly failed in his assigned duties, sources reported Monday.

"It's so much work taking care of Evan, and Mark just refuses to help out as much as he should," said Sharon Thomas, who endured a long, agonizing childbirth to put an end to the couple's constant bitter arguments. "It's so frustrating. I don't get any time to myself because Evan needs attention like 24 hours a day."

"I never asked for this," Sharon added

According to sources, Mark Thomas, 32, had always wanted a healthy, happy, completely normal son to provide a quick and easy fix to all of his marital problems. However, rather than allaying their trust issues and instantly making everything all better, Evan has reportedly driven a deeper rift between his parents by prompting fights about who is to blame for his condition.

"The doctors are constantly telling us that it's not anyone's fault, but if you'd ever met Sharon's brothers, you'd know that something's not quite right on that side of the family," Mark said. "We probably shouldn't yell in front of him as much as we do, but he doesn't really pay much attention and it honestly doesn't seem to bother him."

"In fact, nothing seems to bother him," Mark continued.

Although Evan was only diagnosed with autism six months ago, Mark said it was clear right after bringing him home from the hospital that something was wrong with their son, since their lives did not take a dramatic 180-degree turn for the better, lingering disputes did not just melt away, and years of underlying tension were only brought into sharper focus.

The child, who according to his parents rarely smiles or acts cheerful, has left many in the household concerned that he's not committed to mending the broken relationship. Moreover, during the past three years, Evan has reportedly done almost nothing to curb Mark's controlling nature or Sharon's cruel emotional abuse.

Evan has also failed to utter the words "mama" or "dada," thereby ruining any chance his parents might have had at forging an instantaneous, all-healing bond.

"Nobody told me I'd be so exhausted and cranky all the time," said Mark, who had anticipated that a son would create the mutual respect that his marriage has always lacked as opposed to making him feel overwhelmed and trapped. "Now, I just get nagged about never dealing with Evan after I bust my ass at work all day."

Mark and Sharon also complained that the highly structured schedule they're forced to keep to prevent Evan from "acting up" has severely strained their social life, causing them to miss a recent Super Bowl party at a neighbor's house that all of their friends without special-needs children were at.

In 2006, before giving birth to Evan, the awful couple attempted to salvage their relationship by purchasing an American pit bull terrier puppy. But the dog, who was reportedly a real pain to take care of, lacked the discipline to put in any work on their miserable marriage and always demanded too much affection.

Family members told reporters they weren't surprised Evan has not yet managed to transform the couple's dysfunctional marriage into a healthy and loving one.

"Oh God, they should never have had a kid," Evan's grandmother Janet Harmon said. "She should have gotten her tubes tied like she threatened to do in the first place."

Mark and Sharon said they were currently trying to get pregnant again in hopes that a new baby would take off some of the pressure of raising Evan all alone.