The actress joins a Web chat with Oprah Winfrey and author Eckhart Tolle

Oprah Winfrey‘s self-help Web chats with author Eckhart Tolle are now drawing some celeb guests: Jenny McCarthy showed up this week to talk about her relationship with 5-year-old son Evan.

McCarthy, who spoke to PEOPLE last year about her struggles with her son’s autism, discussed Tolle’s book, A New Earth: Awakening to Your Life’s Purpose, which Oprah picked as her latest Book Club selection. (Winfrey liked it so much she launched a 10-week Web “class” around it.)

“I read this book when it first came out and this was one of my big wake-up calls,” says McCarthy, who spoke about the need to simply “be” with him – and whether that was enough to be a good mom. (See the rest in the video above.)