The Mad Men season five premiere revealed that Don Draper has gone through a lot of changes in the previous year. He's married Megan, traded in his suburban home for a mod 60s apartment, and acquired yet another Bobby. The episode featured actor Mason Vale Cotton as Don's son, making him the fourth actor to play the role. Maxwell Huxabee and Aaron Hart played Bobby in season one, then Jared S. Gilmore managed to remain on the show for two whole seasons. However, during Mad Men's long hiatus, Gilmore left to take a role in the series Once Upon a Time, bringing back the Drapers' middle child mayhem.
Outside of soap operas, Bobby Draper may be the most re-cast TV role in history, but the practice actually dates back to the Mad Men era. The most infamous re-cast is that of Darrin Stephens in Bewitched. The role was originated by Dick York, but when a back injury forced him out of the show, Darrin magically reappeared as Dick Sargent. Some complained the show was never the same, just as when The Fresh Prince of Bel-Air swapped Janet Hubert-Whitten for Daphne Maxwell Reid as Aunt Viv. While the character was originally an outspoken career woman, she was reincarnated as an easygoing stay-at-home mom and started making fewer appearances on the show. Most recently, the twins Jaden and Ella Hiller, who played Lily in the first two seasons of Modern Family,were pulled from the show because they didn't enjoy acting. Four-year-old Aubrey Anderson-Emmons took over the role.
Often, shows play re-casts for laughs. Sarah Chalke replaced Lecy Goranson as Becky Connor on Roseanne, but Goranson returned to the role occasionally. Asking Becky "Where the hell have you been?" became a running gag, and both actresses made an appearance in the show's finale. That '70s Show followed suit after Lisa Robin Kelly left the role of Eric's sister Laurie and was replaced by Christina Moore. Eventually the character was phased out entirely and characters started giving excuses for why she never appeared on screen. Having two Martas and two Anns in Arrested Development actually made sense thanks to the show's use of meta comedy. Marta starred in Spanish language soaps, in which actors are frequently re-cast, and Ann's replacement underscored how forgettable she was.
Frequent re-casting definitely isn't the worst fate to befall a TV character. In fact, Bobby Draper should consider himself lucky, since so far he's avoided another danger for TV kids. After being re-cast, Richie's older brother Chuck on Happy Days was sent off to college and never spoken of again. If Bobby doesn't watch, it Sally might literally make her little brother disappear.