Bismihi Ta`ala
ONE SHEEP IS NOT SUFFICIENT FOR QURBANI OF THE WHOLE FAMILY.

The beloved prophet Swalallahou `Alaihi Wasallam did qurbani(udhiyah) for all the years of Madinah Munawarah. Every year, when the days of qurbani was approaching, he would send someone to buy 2 sheep.(Muslim) It is reported in Tirmizi that the beloved prophet SAW did qurbani for all the 10 years he stayed in Madinah. Although in the beginning of Madinah, it seems that the obligation of the qurbani was only on the prophet SAW, but in later years, qurbani became wajib upon sahabas also.
Imaam Bukhari r.a. brought in his Sahih that sahabahs in Madinah also used to feed animals for qurbani to make them become fat and well bred:
وَقَالَ يَحْيَى بْنُ سَعِيدٍ سَمِعْتُ أَبَا أُمَامَةَ بْنَ سَهْلٍ قَالَ كُنَّا نُسَمِّنُ الْأُضْحِيَّةَ بِالْمَدِينَةِ وَكَانَ الْمُسْلِمُونَ يُسَمِّنُونَ
بخاري

But the proof that it is wajib on every single adult rich member of the family is found in Mustadrak Hakim:
أخبرنا أبو بكر بن إسحاق الفقيه ، ثنا إسماعيل بن قتيبة ، ثنا أبو بكر بن أبي شيبة ، ثنا النضر بن إسماعيل البجلي ، ثنا أبو حمزة الثمالي ، عن سعيد بن جبير ، عن عمران بن حصين رضي الله عنه أن رسول الله صلى الله عليه وسلم ، قال : « يا فاطمة قومي إلى أضحيتك فاشهديها فإنه يغفر لك عند أول قطرة تقطر من دمها كل ذنب عملتيه وقولي : إن صلاتي ونسكي ومحياي ومماتي لله رب العالمين لا شريك له وبذلك أمرت وأنا من المسلمين » قال عمران : قلت : يا رسول الله ، هذا لك ولأهل بيتك خاصة فأهل ذاك أنتم أم للمسلمين عامة ؟ قال : « لا بل للمسلمين عامة » « هذا حديث صحيح الإسناد ولم يخرجاه » وشاهده حديث عطية ، عن أبي سعيد » .
مستدرك للحاكم
A sahih hadith of Mustadrak Hakim:
The beloved prophet SAW said: ‘’O Fatimah, stand up and witness your Qurbani(sacrifice). Because the first drop of blood will erase all your sins that you committed. And say:

إِنَّ صَلاتِي وَنُسُكِي وَمَحْيَايَ وَمَمَاتِي لِلَّهِ رَبِّ الْعَالَمِينَ ، لا شَرِيكَ لَهُ ، وَبِذَلِكَ أُمِرْتُ وَأَنَا أَوَّلُ الْمُسْلِمِينَ
INNA SALATI WA NUSUKI WA MAHYAYA WA MAMATI LILLAHI RABBIL ALAMIN, LAA SHARIKA LAH, WA BIZALIKA UMIRTOU WA ANA AWALOUL MUSLIMIN. Translation: Verily my salaah, my qurbani, my staying alive and my death are all only for Allah, Lord of universe. He has no partner. And I have been prescribed for this and i am first to be in submission.(This dua is masnoon at time of slaughter and not Takbeer)
From there, Imraan ibn Hussein r.a. asked the beloved prophet SAW whether the action of qurbani was an action reserved only to the the family of the prophet SAW only? The beloved prophet SAW answered by ‘’No. But it is an established action for all muslim(families).’’(Mustadrak Hakim).
Besides this, know that Qurbani is emblematic to our religion:

وَالْبُدْنَ جَعَلْنَاهَا لَكُمْ مِنْ شَعَائِرِ اللَّهِ لَكُمْ فِيهَا خَيْرٌ
We made for you as symbols of Allah: the big animals of sacrifice(like camels and cows). There are many benefits for you in them.’’(22:36)
The emblematic status brought it to muslims as an obligation and very important. But then the sunnah brought the condition of being rich and having nisaab value for its obligation.

عَنْ أَبِي هُرَيْرَةَ
أَنَّ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَالَ مَنْ كَانَ لَهُ سَعَةٌ وَلَمْ يُضَحِّ فَلَا يَقْرَبَنَّ مُصَلَّانَا
ابن ماجة
‘’One who had the means(to make qurbani) and would not do it, then he should also not come for Eid salaah.’’(Ibn Majah)

Hence Qurbani became wajib on every member of the family who are baaligh and had nisaab value over and above their necessities and debts as at 10th Zul Hijjah, in the morning.

So one sheep or one share is not sufficient for the whole family.

حَدَّثَنَا شُعْبَةُ، عَنِ الْأَسْوَدِ، سَمِعَ جُنْدَبًا الْبَجَلِيَّ، قَالَ: شَهِدْتُ رَسُولَ اللهِ صَلَّى اللهُ عَلَيْهِ وَسَلَّمَ صَلَّى يَوْمَ أَضْحًى، ثُمَّ خَطَبَ، فَقَالَ: «مَنْ كَانَ ذَبَحَ قَبْلَ أَنْ يُصَلِّيَ، فَلْيُعِدْ مَكَانَهَا، وَمَنْ لَمْ يَكُنْ ذَبَحَ، فَلْيَذْبَحْ بِاسْمِ اللهِ
مسلم
This hadith of Muslim Shareef also describe that Qurbani is a rite attached to individual and not to a group or a family: The beloved prophet Swalallahou Alaihi Wasallam made a khutbah on Eid ul Adhaa whereby he said: “One who slaughtered before salaah, then he should redo another animal to REPLACE IT(to be slaughtered after salaah).”

Hence this hadith brings the Obligation of qurbani and also its application on an individual and not a group.

Another hadith of Muslim Shareef also describe the application of Qurbani on individuals and not a family group:
حَدَّثَنِي جُنْدَبُ بْنُ سُفْيَانَ، قَالَ: شَهِدْتُ الْأَضْحَى مَعَ رَسُولِ اللهِ صَلَّى اللهُ عَلَيْهِ وَسَلَّمَ، فَلَمْ يَعْدُ أَنْ صَلَّى وَفَرَغَ مِنْ صَلَاتِهِ سَلَّمَ، فَإِذَا هُوَ يَرَى لَحْمَ أَضَاحِيَّ قَدْ ذُبِحَتْ قَبْلَ أَنْ يَفْرُغَ مِنْ صَلَاتِهِ، فَقَالَ: «مَنْ كَانَ ذَبَحَ أُضْحِيَّتَهُ قَبْلَ أَنْ يُصَلِّيَ – أَوْ نُصَلِّيَ -، فَلْيَذْبَحْ مَكَانَهَا أُخْرَى، وَمَنْ كَانَ لَمْ يَذْبَحْ، فَلْيَذْبَحْ بِاسْمِ اللهِ»
مسلم
“…The one who slaughtered HIS ANIMAL before eid salaah, then he should redo another animal in its place..”(Muslim)
Hence qurbani application is on an individual and not sufficient for his all family.

Every single member of the family that has reached puberty and possessing the nisaab value in his bank account or elsewhere, then he should take his share personally. The father a separate share, the wife a separate share and each baaligh child a separate share each. Read more on the conditions for qurbani to be wajib on islam-qna.org.
Mufti Mackoojee
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