Answer invitations, especially to a walīmah. The Prophet ﷺ said: “When one of you is invited to a walīmah, let him come.” (al-Bukhārī). Answering the invitation is among a Muslim's rights over another (al-Bukhārī) — even a simple meal: “If invited to a sheep's trotter, I would accept.”
العربية: عن ابن عمر رضي الله عنهما أنّ رسول الله ﷺ قال: «إذا دُعِي أحدكم إلى الوليمة فليأتها». (البخاري).
When a Muslim invites you, accept if you can — it honours them and strengthens bonds.