Mom moved to tears by birthday invitation sent home with her son

A Canadian mom was moved to tears after her son brought home a birthday party invitation accompanied by a touching letter penned by a class mom, whom she'd never met.

"It was an ugly cry for me that day," Tricia Klein of Brantford, Ontario, told ABC News. "Yes, I was shocked that someone would take not only the time to write the note, but to be considerate enough to include him with all of his difficulties. It was a wonderful moment."

Klein, 34, a mom of three, said her youngest son Timothy, 7, was diagnosed with non-verbal autism when he was 2 years old. "While it allowed us to access services, the diagnosis was pure devastation," she said. "I went through a long period of grieving...this was not the son I expected to have, or the life I expected us to live. Of course you love your children no matter what, I'm not saying that has ever, or will ever change regardless of what comes our way. At the time I felt robbed, robbed of the toddler years, the milestones of typical childhood and future years to come."