Jack Pratt is always welcome on his mom's book tour!
Faris' bespectacled little guy made a brief but adorable appearance at the signing, where eyewitness Hugo Meng tells ET she was "excited and sweet."
“She was thankful to her fans for waiting for her.” Meng says, noting that the 40-year-old actress gave some of her fans animal toys as gifts.
“She thanked us for coming to support her," Meng adds, remarking that Faris' recent split from Pratt was not discussed. "She gave some readers hugs and kisses during the signing.”
Another eyewitness tells ET that Faris seemed "super happy, enthused and grateful to see all her fans that showed up for her," adding, "She did address the crowd several times ... She took the time to speak to and hug everyone. She also made some jokes and references to her podcast." Like her book, Faris' podcast is also titled Unqualified.
The eyewitness also reveals that Faris had everyone collectively yell "F**k you, Sim!" which is something she does at the end of every podcast episode.
"She was so sweet and genuine," the eyewitness continues. "She really made my night. Totally worth the wait.”
It's great to see Faris -- and her little boy! -- have such a great time with her fans.
Watch the video below for the biggest revelations from her new book.
Reporting by Antoinette Bueno.