A proverb meaning that in urgent situations you should make use of whoever is available (even if it's a parent); prioritize getting the job done over courtesy or hierarchy.
会議の準備が間に合わないと聞いて、部長が『立っているものは親でも使え』と言って手分けするよう指示した。
Hearing that the meeting preparations wouldn't be ready in time, the manager said 'use whoever is available' and ordered everyone to split the tasks.
急な停電で人手が不足していたため、近くにいた人に頼んだ。まさに『立っているものは親でも使え』だ。
Because of an unexpected power outage and a shortage of hands, we asked people nearby for help. It was exactly a case of 'use whoever's available.'
このことわざは実務や災害時に特に当てはまる考え方だ。
This proverb especially applies to practical work and disaster situations.