Abu Hurairah reported The Messenger of Allah ﷺ as saying When a woman gives something her husband has earned without being commanded by him to do so, she has half his reward. (Using translation from Abū Dāʾūd 1687)
"إذا أَنْفقت المرأةُ مِنْ كَسْب زَوْجهِا عَنْ غيرِ أَمْرِه فَلها نصفُ أجرْه" .