A Single parent dies leaving her estate for to 4 siblings, if one of the siblings dies before the estate is decided by the court, do the hiers of the

If the parent dies with will giving the estate to siblings and one sibling dies before the (sibling parent) then the terms of the will determine who gets predeceased sibling's share. If sibling dies after (parent sibling) this will have no effect upon parent's estate.   Note, if there is homestead property involved then if the parent had any minor children at death then the devise of the homestead might be void.