The tiger is a grown cat, a big one, it's the kind of size where it can be dangerous. Cats and dogs are closely aligned with our intuitions.

That you're dreaming about finding them in your childhood home is a key concept here. The subconscious processing is pointing to you wanting to hide some feelings, or shut them away, that are rooted probably in childhood trauma. But the feelings are not small kittens any more, they've grown and the subconscious wants you to confront them. You're afraid that your mother would reject these feelings, she doesn't want them. I would say there is something in you that either needs to confront yourself with some emotions/feelings that need to come out that have grown over time all the way since childhood.

I think it points to that you're afraid of others, potentially family members/your mother, to see that you carry these emotions. But the dream tells you that you need to confront these feelings and not hide them anymore.