The 'Id sacrifice of the members of one household

A man has children, and he has an older son who is married and lives with him. They are employed, and their food and drink are the same. Is one 'Id sacrifice sufficient for both of them?
The members of one household have one 'Id sacrifice, even if they are numerous. So if they are brothers who share the same food and the same house, their 'Id sacrifice is one. This applies even if they have multiple wives, and likewise for a father with his sons, even if one of them is married; the 'Id sacrifice is one.