With lots of attention around her professional and private life, Kate Hudson is no stranger to scrutiny – and teaching her 3-year-old son, Ryder, about the family fame comes with the territory.

"Every once in a while, he'll go, 'Oh my God, mommy, you're on TV, you're on TV!'" Hudson, 28, told PEOPLE at Tuesday's Glamour Reel Moments premiere of her directorial debut, Cutlass, in West Hollywood.

"I don't think he has any understanding of [it]," Hudson said, when asked if he recognizes that she is a Hollywood actress. "I think he's aware that it's mommy's job."

Hudson, who gave birth to Ryder in January 2004 with then-husband Chris Robinson, brings her son with her to movie sets, she says, noting that he pays close attention to what his mother does.

"I watch my son when he goes on set, and [he] watches what we do," Hudson said. "You can't help but be interested in what everybody is doing."

Remembering her own on-set upbringing with Goldie Hawn and Kurt Russell, Hudson says, "People ask me that, about my parents, growing up. I don't ever remember a defining moment where I understood what my parents did. It was their job, like anybody."

In recent months, Hudson has declared dating as a single mom "very different" after filing for divorce last year after six years of marriage. Hudson then dated Owen Wilson for about a year, before splitting in May and picking up with actor Dax Shepard in July.

Tuesday night, Hudson told a reporter that Shepard is a "great guy," but that she didn't like talking about her personal life.

"Less is more," said Hudson, who also, with a smile, declined comment to PEOPLE.