The third series of the sitcom is currently airing on Channel 4, with Carrie reprising her role as Mia, Rob’s mother in the show.
Following her death at the end of last year, Rob has admitted that watching her last scenes back has added another layer of poignancy.
Speaking ahead of Carrie’s final episode, which airs next month, he told Digital Spy: “She’s in most of the scenes in the final episode. She’s a huge driving force in it.
“And in addition to being funny, it’s really quite beautiful, which is weird because then she died. Now in retrospect watching it as we’ve been editing, it’s gut-wrenching because of how poignant everything she does in it is.”
Carrie - best known for her role in the original ‘Star Wars’ trilogy, as well as her later work as an author - died in December 2016, after suffering a heart attack while on board a plane.
‘Catastrophe’ marks one of her last ever appearances on screen, and she’s also set to appear as Leia once again in the upcoming eighth instalment of the ‘Star Wars’ series, ‘The Last Jedi’.
The third series of ‘Catastrophe’ continues on Tuesday (28 March) at 10pm on Channel 4, with the series finale set to air in the first week of April.