、。
If it's too painful, give up and listen to big sister, okay?
Literal
Painful [if-たら] give-up-[and-て], older-sister [attributive-の] request [object-を] listen-[gentle-command-なさいっ].
お姉さん ('big sister') used self-referentially — a woman referring to herself as 'your big sister' to a younger person, typical of friendly/authoritative older-woman speech. ギブアップ is wasei-eigo from 'give up.' お願いを聞く ('to listen to a request = to grant a request') is a set phrase. The small 促音 っ at the end of なさい adds emphatic, clipped delivery.