be made of sterner stuff

To be very strong, determined, or of uncompromising character, especially in comparison to others. Having to take care of both of us growing up, my brother George was made of sterner stuff as a kid than anyone else I knew. I can't believe you let us down at the last minute. I thought you were made of sterner stuff than that! Well, for starters, you can't take everything personally. You need to be made of sterner stuff if you want to survive in this industry.

be made of sterner stuff

(of a person) have a stronger character and be more able to overcome problems than others.

This expression comes from Shakespeare's Julius Caesar: ‘When that the poor have cried, Caesar hath wept; Ambition should be made of sterner stuff: Yet Brutus says he was ambitious; And Brutus is an honourable man’.

1998 Spectator Unlike the Americans, who are inclined to pull all their personnel out of a country at the first hint of trouble, the British foreign service is made of sterner stuff.

be made of sterner ˈstuff

(of a person) have a stronger character and be more able to deal with difficulties and problems than other people: Did she cry? I thought she was made of sterner stuff.