Even though she was poor, she gave him every last bit of money she had.
Literal
She [topic-は] was-poor [although-けれども], meager money [object-を] all him [to-に] gave.
なけなしの金 ('meager savings,' literally 'the money you have that is almost nothing') is a vivid expression for one's last remaining funds. ~けれども is a formal 'although.'