Cai Gao's father was a Cantonese merchant at Macao whose legal wife had borne him no children; Gao's mother was his second concubine [REF].
The use of lou⁵ (, p lǎo, "old") and aa³ (then , p yà or yǎ, but now , ā, "dear ~, dear little ~") reflects the standard practice of Cantonese nicknames.