1 sentence

1. 他们两家早已通过儿女的婚事结为了亲家。

   tā​men liǎng jiā zǎo yǐ tōng​guò ér​nǚ de hūn​shì jié wéi le qìng​jia.

   The two families became in-laws long ago through the marriage of their children.

   Source: Dong Chinese Dictionary