Dominika's birth parents placed her for adoption at The Cradle in Evanston, Ill., where she stayed for five months before Irvine and Tamley were approved as adoptive parents.
"We fell in love with her and brought her home," he said.
Still, parenting has not been easy. Besides facial disfigurements, Dominika has scoliosis, fused shoulders and mild hearing impairment. She's had over a dozen surgeries and procedures.
"It did take an adjustment for us to some extent," he said. "We certainly didn't know what our baby would be like. "
But the hardest part is watching Dominika cope with unwanted attention.
"When she was younger, she was pretty oblivious," he said. "But around 5, she started feeling it more. Kids make remarks or stare. Kids come and point and bring friends to look at her."
Just last week at an indoor playground, a child looked at her face and screamed, "Ewww!"
"When I am on the scene, I make a comment," said Irvine. "We told her that if she hears that, she should let them know it hurts her feelings -- it's an important way to disarm them. She can also introduce herself -- when kids know someone's name, it does help."
Irvine said it was "unrealistic" to expect people to be instantly comfortable with a severe facial disfigurement. "People feed off your attitude and how you act. If you are comfortable, they will feed off that."
In the case of the Charlene Machin, he said no one should judge her for not immediately loving her child, and he was inspired by her sharing the story.
"We need to tell our stories," said Irvine. "More of us are living openly out there and it is easier for families like the one in England to get to a place of acceptance when they are surprised by disability."
Today, Machin is unequivocal in her love for both Harry and Oliver, but it wasn't' easy.
In the first stroller rides around town Harry faced unwelcome points and stares. Some even screamed after seeing the child, she said. Machin blamed herself.
But things changed when the twins were about 18 months old. Machin was in a mother's store when children surrounded her to look at the twins.
"I felt like the Pied Piper as I walked through the store with them behind me, staring and pointing," she said. "I'd had enough. It was time to help Harry face the world. I swung the buggy round and said, 'This is Harry'.
"The children asked what was wrong with him, so I told them. And afterwards I felt stronger. Instead of trying to hide my son away, I'd faced it head-on, and I felt better."
Harry has now had three successful surgeries to reposition his eye socket. Next year, doctors will stretch his eyelid and fit it with a prosthetic eye.
His mother said she recently overheard Oliver say to one of Harry's tormenters, "He's my brother. It doesn't matter what he looks like."