ㄅㄞˊㄊㄡˊㄒㄧㄝˊㄌㄠˇbáitóu‑xiélǎo

白头偕老
  1. 夫妻相親相愛共同生活直到年老用作婚禮頌詞 新人永浴愛河白頭偕老」。

(to live together until the)​ white hairs of old age (idiom)​; to live to a ripe old age in conjugal bliss, until death do us part