Blood is thicker than water is a medieval proverb in English that means that familial bonds will always be stronger than bonds of friendship or love. The oldest record of this saying can be traced back in the 12th century in German. The phrase was first attested in the United States in the Journal of Athabasca Department (1821)."[5] On June 25, 1859, U.S. Navy Commodore Josiah Tattnall, in command of the U.S. Squadron in Far Eastern waters, made this adage a part of U.S. history when explaining why he had given aid to the British squadron in an attack on Taku Forts at the mouth of the Pei Ho River, thereby abandoning the strict American policy of neutrality that had been adopted in the Second Opium War after the Battle of the Barrier Forts.[6]
“血浓于水”是中世纪英语谚语，起源最早可追溯到12世纪的德文。
这句话在美国文档中的首次出现，是记述第二次鸦片战争中美国舰队指挥官Tattnall在解释他为啥帮英国舰队作战时提到的，要知道第二次鸦片战争美国政府是严格持中立立场的。
当时英军在海河攻击大沽口炮台遇挫，起先美军还只是帮着救护一下英军伤员，后来就直接赤膊上阵开枪开炮了。
我老再次强调，白皮尤其是西北欧的白皮，也有是所谓上等白皮是非常讲究血统的，不是纯生意人，有时为了帮亲不帮理，完全可以做到脸都不要，更别提讲啥法理了。。。
Blood is thicker than water is a medieval proverb in English that means that familial bonds will always be stronger than bonds of friendship or love.
The oldest record of this saying can be traced back in the 12th century in
German.
The phrase was first attested in the United States in the Journal of
Athabasca Department (1821)."[5] On June 25, 1859, U.S. Navy Commodore
Josiah Tattnall, in command of the U.S. Squadron in Far Eastern waters, made this adage a part of U.S. history when explaining why he had given aid to
the British squadron in an attack on Taku Forts at the mouth of the Pei Ho
River, thereby abandoning the strict American policy of neutrality that had been adopted in the Second Opium War after the Battle of the Barrier Forts.[6]