What does になると mean here? Is it a quote?

Question

甘えん坊で、泣き虫の栄五ちゃんは、俺を慕ってくれていた。俺の家の子になると泣いてくれたくらいだ。その涙は幼い俺の胸を歓に満たした。

The character mention how the character called 栄五 used to cry for him and be very affectionate as a kid. I am confused by this line here:

俺の家の子になると泣いてくれたくらいだ

is "泣いてくれたくらいだ" he cried to the point however, I am confused on why 子になる here is used? As far I know the kid in question was not adopted into his family. My reading would be like "He cried enough that he wanted to be my family" but grammar wise it makes no sense=

Answer 1

The と is quoting 俺の家の子になる.

俺の家の子になると泣いてくれたくらいだ

means to the extent/point that he cried (saying that) he'd be my child (a child of my family). くらいだ is correlated with 慕っていた. That is, he like me so much that he cried saying....