عَنْ عَبْدِ اللَّهِ بْنِ عَمْرٍو قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «لَا يَرْجِعُ أَحَدٌ فِي هِبَتِهِ إِلَّا الْوَالِدُ مِنْ وَلَده» . رَوَاهُ النَّسَائِيّ وَابْن مَاجَه

‘A’isha reported the Prophet as saying, "Give presents to one another, for a present removes grudges.” …transmitted it. (Mirqat, 3:380 says that Tirmidhi is the source in which this tradition is found. I have looked for it with the help of the Concordance, but have been unable to find it.