Calhoun Johnson is the son of Pam Tucker and Bo Johnson. He was born in Mitchell and Cameron's house. His mother carried him for nine months without telling her family about being pregnant because they didn't want her to get back together with Bo and she didn't want them to think she was a screw up.
As a newborn, Calhoun did not sleep well, making Pam exhausted. ("All Things Being Equal")
He appeared in the episode "Clash of Swords", having appeared a little older. According to Mitchell and Cameron, Calhoun was “freakishly strong” since he was able to knock them both them in a hug. Mitchell was even revealed that despite Calhoun only having two teeth, he could eat a whole chicken. At the end of the episode, Mitch and Cam decidee to take care of him until Pam was out of jail.
He appeared again in the Season 10 premiere, "I Love A Parade".
Calhoun returned to live with Pam when she was released from prison.