I don't really blame the elder brother. I also wish he noticed but everyone were just suffering from the trauma of losing their parents and handling that depression. Especially him as he is the new heir, has the most pressure and has more responsibilities at a young age.
I'm mad the elder brother didn't see how the aunty torture Hari/replace the maid and servants in the house.
They even prevent 2nd brother to get any communication from the 1st brother. So angry