The common crossword answer for the clue "be kind" often is "NICE." This was specifically noted as a 4-letter answer used recently in several crossword puzzles including the Universal Crossword and the NYT Mini Crossword.

Another related answer, especially in a philanthropic or charity context, is "DOGOOD," which appeared in a NYT Mini Crossword clue "Give to charity, be kind to others, etc.".

If the clue is in the context of a phrase or Shakespeare reference, "BENIGN" has also been used for "be kind".

For the NYT Mini Crossword on September 2, 2025, the exact answer for "be kind" was not found explicitly in the available data, but "NICE" is a strong general fit. So for "be kind" in the NYT crossword context, the most likely and general answer is: NICE If more context is available (like number of letters or crossing letters), it could refine the answer further.