I think English word "Brother" or "Sister" should be very interesting for Japanese. Brother is such a simple and easy word and we all know it, however, we cannot translate it exactly into Japanese.
This is because Japanese language doesn't have a word which means both "older brother" and "younger brother." In Japanese, they are expressed as two different words (Ani/Onii-san & Otouto/Otouto-san) and thus we need to know whether he is "younger brother" or "older brother" when we translate a word "Brother" into Japanese. But sometimes when I encounter a word "brother" while reading a book, I stay curious whether he is older or younger.
The reason why Japanese has two different words for brother is because of the culture (influenced by Chinese culture) to respect elderly people and the first son of the family used to be valued so highly. Therefore we need to know whether they are older or younger. Without knowing it, sometimes it's hard to talk.
This can be another example of how people in different cultures are interested in the certain things. And the word "brother" is kind of opposite example of the word "horse/uma" As I mentioned it yesterday, in English, there are so many words for "horse." But in Japanese, they are all expressed as one word "Uma." Whether it's pony, horse, colt, stallion, we all call it "Uma."
Then if Japanese need to specify the horse, we add adjective. This is just like adding adjective of "elderly" or "younger" to the brother or sister, when English speaking people need to specify its meaning.
This afternoon, my friend and his wife came to Koloa from New York. For me it was very interesting that they used different words for chicken when they see them. They were "Rooster", "chicken" and "hen." It was obvious they see chickens as they notice different types of chicken.
On the other hand, I realized I had seen "chicken" as same. Whether it is rooster or not, they have been all "chicken" for me. I call them all as "chicken" ,too.
Why? This is because the equivalent of chicken in Japanese, "Niwatori" means both "hen" and "rooster." But that's not all. I think this is because I don't care Chickens!