".She explained: "It's very much two steps forward, three steps back."If I think back to where we were in March 2020, when Derek's lungs were solid with infection and his infection rates were the highest doctors had seen in anyone who has lived."Reflecting on how far he has come, Kate added: "We're undoubtedly in a more positive place."After Kate announced a breakthrough in Derek's health back in October as he uttered his first words, Kate admitted his recovery has been "emotionally challenging".She told The Sun: "The emotionally challenging thing is that we're waiting now to see what happens next; somehow it's even more agonising now there's been this breakthrough."We have greater hope now, but also greater fear of him slipping.