A 1/4 pound of real butter may do the trick, never thought about that till now.
The plant fat calls for all the bile the liver has and that is why the stones come rolling out after all the Epsom Salts is used to relax the bile ducts.
Now why animal fat would not work? It may not be absorbed as quickly by the liver, I have no idea, it surely can do zero harm to self experiment with this and who knows, you may find a better way. Let us know what happens.