Answered by Shaykh Faraz Rabbani
I was today quoted the following hadith (Sahih, Tirmidhi):
Abu Ayyoob: “At the time of the Messenger of Allaah (peace and blessings of Allaah be upon him), a man would sacrifice a sheep on behalf of himself and the members of his household, and they would eat from it and give some to others.” (Reported by Ibn Maajah and al-Tirmidhi, who classed it as saheeh)
This is in contradiction to the answers on Sunnipath that say that every adult in the household (i.e. both the husband and wife) should give a separate sacrifice.

Walaikum assalam wa rahmatullah,
In conjunction with other primary evidence, these hadiths are understood to refer to situations where other household members did not have sufficient wealth of their own to be obligated to sacrifice–or that the family members pitched in together to have enough to sacrifice.
Faraz Rabbani