Trump's father was worth about 250 million at his death. Donald had three siblings, at that time and his mother was still alive, IIRC. Ergo, his father's estate was larger than you imagine, but there were far more to inherit the estate's money/etc. !
Whatever Trump is now worth, the vast majority of it is of his own making and hard work.
Trump’s father didn’t die until 1999.
Long after Donald became successful.