We can enroll a family for a family membership fee directly from the customer card of the head of the family.
By clicking on Customers > Customers we will access list of customers.
We can now click on the edit button 
next to the customer we want to identify as head of the family for the purpose of this membership.
We will then go to the option 'Fees' to create a new one:
Here we will find the page below with the following options:
From here we will select the type of subscription we want and the type of tariff applied.
We can select the day that we want it to take effect, for example the 15th day of the month or the day it has been created ...
In the date of permanence, we can leave it blank or select a date, in case we have a minimum period of stay.
In the field 'Members in the seasonal ticket' we can type in the name of the customers we want to add as members. We can only add in this field people that are identified as related to the head of the family.
Within the section of Initial fee we will be able to select if we want it fractioned or not.
We can also choose when we want to start collecting the following fees, as well as the form of Payment.