Historically, minorities were allowed to have more children than Han Chinese, FYI. Han only reached the same child allowance recently.
ethnic Korean from north east China here, many of my relatives had 2 children while our Han neighbors only had 1
> When the policy was implemented, 26 [out of 31] Chinese provinces allowed ethnic minorities to have an additional child.
There were other exemptions too - for example, rural farmers could often also be exempted, particularly if their first child was a daughter.