Why was Zenitsu given a sparrow?

Why was Zenitsu given a sparrow? When looking at the symbolism in Japanese culture, sparrows represent ‘the soft demeanor of deep thinkers’ and are often considered to bring good fortune- and Zenitsu’s name literally includes the kanji for good!

When looking at the symbolism in Japanese culture, sparrows represent ‘the soft demeanor of deep thinkers’ and are often considered to bring good fortune– and Zenitsu’s name literally includes the kanji for good!