Sgt. Frog Episode 91: Keroro, the New Year, Birth of New Keroro / Koyuki, Granny is Coming
Episode 91 of 358 of Sgt. Frog, aired January 6, 2006, 25 minutes. Available with English subtitles and dub where released.
Episode summary
Kululu`s latest gun turns serious ninja Dororo into a slacker and slacker Keroro into a serious disciplinarian. And when the Natsumi`s grandmother pays a visit for New Year`s, Koyuki develops a special bond with her. Source: crunchyroll