My brother stole everything

My father passed last month. My brother 48 never left home. My mom passed in 1999. My sister and I knew how upsetting it was for my dad to mention a will. We asked nothing. Found out just from words no paperwork that my brother convinced my dad to sign over his house. Add my brothers name to his bank account to help him while he was battling multiple illness. Cancer and heart disease. My brother says there's a will but he's executor and doesn't have to file it for two years. We also found a joint account statement in the mail. Didn't open it but its with his friend who buys property and is quite wealthy. We were told there wasn't much money in dad's account which is not believable on a 5k a month pension and a 735k home paid in full. We had been believing my brother as my dad was failing when he told us dont worry dad provided very well for his daughters. We have no idea what to do. Are still so sad and hurt. Again we've seen nothing my brother has hidden my fathers paperwork and info.