By Lucretia Munro Doctor Who star Ncuti Gatwa has broken his silence on social media after his co-star Millie Gibson was axed from the show. Millie, 19, who had previously starred in ITV soap Coronation Street, made her debut appearance as the Time Lord’s assistant in the 2023 Christmas special. In May this year Ncuti will take over the iconic role but Millie’s character Ruby has been reportedly replaced by newcomer Varada Sethu for his second series. Once news emerged of Millie being dropped, the actor took to social media and shared a picture of him and Millie and penned: “My lil” accompanie…