Family Advisor accounts in Canada can have accounts for up to 5 family members under the advisor umbrella. However, the number of accounts which can be under the Family Advisor structure can be greater than 5 provided that the additional accounts to the same 5 individuals.
For example, if a Family Advisor account had 5 family members under the advisor umbrella and each member had an individual account, it would be possible to add a TFSA account for one of the same family members. However, to add additional accounts, the FA will need to send an invitation link for the application to the client. Once the additional account is opened, then the two accounts will need to be linked together resulting in one username.