Today Caillou learns that being a part of a family is something very special. Dad lends Caillou his old camera and helps him take pictures of every member of their family - including Gilbert. Looking at the photo album, the family remembers when Gilbert was a kitten and first came to live with them. When Mommy and Rosie go out for the day, Daddy and Caillou have plans of their own. They are building a surprise for Mommy that requires a lot of father-and-son work. When Caillou and his family go to the zoo, Caillou is thrilled to see that animals have families too. Also, Caillou and his family go away for a weekend of camping in the woods.