all one's family; the whole family
Used to refer to one's own entire family, often in formal greetings or announcements.
My whole family wishes you all good health.
New Year's greetings from all of my family.
Similar meaning but uses 家族 (family) instead of 家内 (one's household). 家内一同 is more traditional and humble, often used in formal letters.
Compound of 家内 (かない, 'one's family/household') and 一同 (いちどう, 'all members').