YOU SAID:

there once was a boy whom went to my wagon

INTO JAPANESE

かつて私のワゴンに行った少年がいた

BACK INTO ENGLISH

There used to be a boy who went to my wagon.

INTO JAPANESE

以前は私のワゴンに行った男の子がいました。

BACK INTO ENGLISH

There used to be a boy who went to my wagon.