It's fun to have guests on New Year's Eve is an episode of the 1981 Ninja Hattori-kun anime.
Kenichi's uncle visits for New Year's Eve and causes problems for the kids. After the gang chase Kenichi's uncle away, Kenichi's great - uncle and second cousin visit. While the great-uncle has tea with mum and dad, Hattori and the rest of the gang have to keep an eye on Kenichi's cousin. At first, the cousin is a bit of a handful, but in the end, things work out better.