The Horse That Left the Show

Remember when Guy gave Marian a brand new horse? And she was like "I don't like surprises" I have a question...WHAT THE FRICKIN HECK HAPPENED TO IT? Like after two episodes it just disappeared and she had her dappled grey horse back. True, I like that her first horse more, but that one just disappeared. It was probably because Lucy Griffiths was more comfortable on the other horse.