Isn’t it being coward of Alicia Silverstone to cancel her cameo role as a doctor in the TV show “How I Met Your Mother“because she learned that the Pop Princess Britney Spears will be joining her as the doctor’s receptionist Alicia was supposed to play a hot doctor that lead star Ted, played by Josh Radnor, and has a serious crush on. Report stated that her role is now being filled in by actress Sarah Chalke and that the main reason why she bailed out of the role is because she was afraid that Britney will overshadow her. On the other hand, report also suggested that Britney is having a lot of fun in doing the said TV show.