Thank you for your question
My name is Clare
I shall do my best to help you but I need some further information first.
Why has there been a 20 year delay in dealing with the Estate?
In fact C should be reminded that as an Executor he is personally liable to A and B in respect of the sums due to them under the terms of the Will
Indeed if he does not wish to disrupt the status quo then he may wish to considering "buying out" half of the house so that A and B have the money and he and D own the house in unequal shares
If he does not wish to do that then A and B can apply to the Court to have C removed as an Executor due to his failure to act in respect of the sale.
B can then apply for an Order forcing D to leave so that the property can be sold.
I hope that this is of assistance - please ask if you need further details
That is indeed the case