We set out in the state of Ihram for Hajj along, with Messenger of Allah ﷺ. He commanded us that seven persons should join in a camel and a cow for offering sacrifice. (Using translation from Muslim 1318b)
خَرَجْنَا مَعَ رَسُولِ اللهِ ﷺ مُهِلِّينَ بِالْحَجِّ فَأَمَرَنَا رَسُولُ اللهِ ﷺ أَنْ نَشْتَرِكَ فِي الْإِبِلِ وَالْبَقَرِ كُلُّ سَبْعَةٍ مِنَّا فِي بَدَنَةٍ