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Please don't compare me with my brother.
Literal
I [and-と] older-brother [object-を] don't-compare [please-ください].
比べる ('to compare') can take と or を differently depending on structure. Here 僕と兄を ('me and brother' as a joint object) is the object of 比べる. The 'joining' use of と inside the を-marked object is parallel structure: both entities bundled as the target of comparison. A resigned plea often heard from younger siblings.