Soldier-on Definition

verb

(idiomatic) To continue or persist, despite adversity or difficulty.

He soldiered on through the night, working hard and not sleeping.

Wiktionary

(idiomatic) Continue on with your life after an event as if nothing happened.

First boy:What do I do? I was playing in the house when I wasn't supposed to, knocked my mother's vase over and it broke. She thinks it just fell. How do I tell her?Second boy: It was a cheap vase; telling her will only make things bad for you. She doesn't need to know. Keep your mouth shut, soldier on and take it to your grave.

Wiktionary