The breaker box at my brother's house is well marked and balanced except when a breaker is tripped half the house goes out. I'm currently living on the third floor of his house. When I turned on a small fridge the room went out as well as the stairwell, hall light, kitchen (including a separately breaker-ed microwave) and basement lights. Could all of these be on one breaker?

My brother swears it wasn't always like that and that since an ugly divorce things have been done to the house. I always thought he was paranoid but I have seen a couple of things that make me wonder.

I have traced back and nothing jumps out at me, no Uh-Oh's. Reading before about neutrals being bundled together made sense.

Any additional guidance, direction would be greatly appreciated.