ʿAbdullah bin ʿUmar said, "Messenger of Allah ﷺ said, 'Accept the marriage invitation if you are invited to it.' " Ibn ʿUmar used to accept the invitation whether to a wedding banquet or to any other party, even when he was fasting.
قَالَ رَسُولُ اللَّهِ ﷺ أَجِيبُوا هَذِهِ الدَّعْوَةَ إِذَا دُعِيتُمْ لَهَا قَالَ كَانَ عَبْدُ اللَّهِ يَأْتِي الدَّعْوَةَ فِي الْعُرْسِ وَغَيْرِ الْعُرْسِ وَهْوَ صَائِمٌ
I heard Abdullah b. Umar (Allah be pleased with them) narrating that Messenger of Allah ﷺ said: Accept the feast when you are invited to it. And Abdullah (b. Umar) used to come to the feast, whether it was a wedding feast or other than that, and he would come there even in the state of fasting.
قَالَ رَسُولُ اللَّهِ ﷺ أَجِيبُوا هَذِهِ الدَّعْوَةَ إِذَا دُعِيتُمْ لَهَا قَالَ وَكَانَ عَبْدُ اللَّهِ بْنُ عُمَرَ يَأْتِي الدَّعْوَةَ فِي الْعُرْسِ وَغَيْرِ الْعُرْسِ وَيَأْتِيهَا وَهُوَ صَائِمٌ
[Machine] The Messenger of Allah ﷺ said, "Respond to the caller when you are invited." He said, "And Abdullah used to attend invitations, whether they were wedding celebrations or not, even while fasting."
أَنَّ رَسُولَ اللَّهِ ﷺ قَالَ «أَجِيبُوا الدَّاعِيَ إِذَا دُعِيتُمْ» قَالَ وَكَانَ عَبْدُ اللَّهِ يَأْتِي الدَّعْوَةَ فِي الْعُرْسِ وَفِي غَيْرِ الْعُرْسِ وَيَأْتِيهَا وَهُوَ صَائِمٌ