stand tall - Idioms - by the Free Dictionary, Thesaurus and Encyclopedia.
I think you should first check the idioms or phrasal verbs and if you still can't figure out what the sentence means only then it would be more appropriate to ask it on the forum.By this way we can make the forum more efficient.
As for your question, I guess you should give us its context. Are there any sentences precede or succeed this one?
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