Other than small children, all family members should have and carry their own bug-out bags because family members might get separated in a disaster scenario, bug-out bags contain person-specific items like clothing/toiletries/medication, and putting an entire family's belongings in one bag for one person to carry would generally be impractical.

For a recent discussion of how to customize bug-out bags for different family members, please see this thread posted four days ago: https://www.reddit.com/r/preppers/comments/1lrryu4/bob_for_family_members/