When Christianne Boudreau's son, Damien, converted to Islam, adopted a strict set of rules and grew his beard out four years ago at the age of 17, she was accepting and open-minded.
But she noticed other changes in Damien's behavior: He wouldn't come to the dinner table if the family was drinking wine. He started taking phone calls outside and became withdrawn. Then, he stopped coming home altogether.
"I just saw it as a phase he was going through," Boudreau told NBC News.
What she didn't know in 2011 was that her son, who grew up in a Catholic household, was becoming radicalized. Boudreau said she believes he was first introduced to ISIS extremism by someone in their home city of Calgary, Canada, and then lured in further over the Internet by ISIS propaganda in the form of texts and slickly produced videos.
Her experience is echoed in other recent cases that have gained notoriety, as law enforcement tackle the problem of homegrown extremism and would-be terrorists hailing from the U.S., Canada and the U.K. attempting to join ISIS.