By Lindsey Riley Published: Feb 3, 2014 at 10:27 AM PST
"When they were younger, it was very frustrating," he said. "We thought we were doing something wrong. It was very stressful."
His autistic children fall on different ends of the autism spectrum.
"With Kyle, it's easier for him to overcome social interactions," Rust said. "With Sandra, it's kind of the extreme. For the longest time she would not play with someone unless it was her brother or sister. She would play next to them, but that alone was a milestone."
Small accomplishments are big victories for a family like the Rusts.
And with a diagnosis but not known cause, parents like Rust are left to wonder what caused their child to become autistic.
Vaccines have long been villified by some people in the autism community for having a possible link to the disorder.
Actress Jenny McCarthy has been very outspoken about her opinion on the issue.
"Without a doubt in my mind, I think vaccinations triggered Evan's autism," she told CNN.
McCarthy stood by this belief for years, using her celebrity to spread her message.
"Isn't it ironic that in 1983, there was 10 shots and now there's 36 and the rise of autism happened at the same time?" she told Larry King. "Parent after parent after parent says, 'I vaccinated my baby, they got a fever and then they stopped speaking.'"
Through the years, many parents have decided not to vaccinate their kids because of the perceived risk.
Some doctors say that has now put people at risk of contracting diseases that otherwise would have been supressed by the vaccines.
That's one of the reasons so many doctors and pediatricians disagree with the views McCarthy espoused.
"Vaccines work," said Dr. Pilar Bradshaw. "Vaccines are safe."
What's dangerous, she said, is taking a celebritiy's opinon as fact.
"That's just setting you and your child up for troubles because instead of going with research you're going with voodoo belief," she said.
Bradshaw said that years ago a British doctor published data connecting a vaccine to autism. That doctor later admitted his research was unfounded.
New research suggests autism may be linked to the father's genetics, but much remains uncertain.
But opinions on the issue remain as common as a certainty about the cause of autism is rare.
"I think vaccines played a role," Rebecca Middleton said on the KMTR Facebook page. "Not all cases are genetic. It was like night and day with them. One day they were typical developing babies and the next they weren't."
"To say vaccines cannot cause autism is ignorant," Shasta Haley said. "Constantly pharmaceuticals are being removed from treatment based on new found evidence of adverse affects whether slight or great risk."
The Rust family believes the autism in their family is purely genetic. They vaccinate their children.
The most important thing to Rust and his family is for other to understand that people with autism are just looking at life through a different window.
"You can look at a picture, turn it upside down," he said, "and you'll see something totally different."