so I'm working on a project right now that involves multi-user persona, meaning that our personas are actually families (more than one person). This is the first time that I've met this kind of user, I tried searching online to find dynamics of creating such persona but couldn't find anything. So I'm wondering if anyone has experience with creating a persona that describes multiple people like families.
 the project I'm working on right now is a home design application, it helps people visualize their ideas and share it with others. As you know, home design usually takes place in homes of couples, mostly families having children. Our approach is that we want users to share their ideas with each other and with an outside community. So what I meant by multi-user persona is people who will be using our product are actually families as a whole, not each person on his/her own. So when developing a persona, I think it's not the right move to consider that eventually each one will be using the application on his own. There are some dynamics between family members involved in home design decisions.
So my question again: how do I develop such a persona that includes more than one user? (Think of Disneyland, most of the users visiting it are families and couples, so trying to think of each user on his own would not be considerate enough) I hope this clears up the confusion.
You still need to design this for individual personas ("we want users to share their ideas with each other").
Families often go grocery shopping together, but one person usually has the ultimate purchasing decision power (as we notice when a toddler throws a tantrum because Mom won't buy his favorite candy). Your research can consider different types of families, and the different kinds of members in each of those types, but individual users with their individual problems and motivations sharing ideas with each other (even while presenting externally as a "family unit") are who you'll need to design for.
I think there's often a feeling that having too many personas is a bad thing, and we have to streamline them as much as possible. But mapping out all the different personas who would 1) be purchasing a home, 2) be looking at home ideas and 3) have some purchasing decision power will help you decide which ones are a priority, and which are not. (Your app exists to make money, and a 9-year-old user might not be as profitable as her mom for your ad partners, as an example).
By all means, if you see family-based clusters of personas, you can label and name them and map their common traits. But families aren't users. People are.