If you love slice-of-life anime and you didn't like Clannad:After Story tragedic and complex plots, then you like Usagi drop. This story is about a grandson who takes in his grandpa's illegitimate daughter, (I know the plot sounds kind of lame). But , believe me, you will enjoy how the story develops. Usagi drop is a very realistic in terms of the relationship between the grandson and his grandpas' daughter(or his aunt to be literal). There aren't any over dramatic scenes-- those annoying scenes that are too emotional or simply out of point.
It is like the writer of the story painted on his/her canvas every part of the story from a real-life situation without removing or adding any extra details. The art of the story itself seems to speak in a similar way.
Overall, Usagi Drop is a lighthearted and entertaining story which no one with a thing for slice-of-life genres should miss out.