Sussex police officers are searching private land in the search for Laurel Aldridge.
The sister-in-law of The Office actor Mackenzie Crook was reported missing on February 14. Mr Crook said his family are "clutching at straws" after appearing on Good Morning Britain on Tuesday.
Despite this, he said the family are "determined and driven" to find Laurel. He added that he believes the disappearance could be linked to her ongoing chemotherapy treatment.
