I would imagine that using foxes give you a lot more to work with though. Foxes in nature live in pairs or small groups. The children stay around the parent for a long time. So they already have mechanisms in place for social behaviours. (And even if they are not expressed, there probably are some latent possibilities shared among mammals? E.g. this article about the evolution of housecats notes that they independently evolved a lot of the same behaviours that lion prides use to socialise, even though wildcats are solitary.)
I would imagine that using foxes give you a lot more to work with though. Foxes in nature live in pairs or small groups. The children stay around the parent for a long time. So they already have mechanisms in place for social behaviours. (And even if they are not expressed, there probably are some latent possibilities shared among mammals? E.g. this article about the evolution of housecats notes that they independently evolved a lot of the same behaviours that lion prides use to socialise, even though wildcats are solitary.)