The Messenger of Allah ﷺ said, "The finest of what you consume is from your own earnings, and indeed your children are part of your earnings."
حدثنا أبو بكر بن أبي شيبة حدثنا ابن أبي زائدة عن الأعمش عن عمارة بن عمير عن عمته
قال رسول الله ﷺ إن أطيب ما أكلتم من كسبكم وإن أولادكم من كسبكم
[Sahih]. Tirmidhi transmitted it in the Book of Rulings, chapter on what has been reported that a father may take from his child's wealth, hadith no. 1358, from the hadith of Yahya bin Zakariya bin Abu Zaida with this wording, and he said, hasan sahih, and Dhahabi graded it sahih. It is also cited in Nayl Maqsud, hadith no. 3528, and in the takhrij of Musnad Humaydi, hadith no. 247.