Transition to big sister

Hey I am currently 37 weeks so not long now until baby’s arrival. Our first and only other daughter is 5. She has been really excited about becoming a big sister but has been extra clingy to me the last couple of months. Tonight she became really upset and tearful at bedtime and told me how worried she is, that she’s ‘not ready to share mummy’ and is scared she will feel left out 💔. We’ve talked a lot about how mummy’s love her her won’t change and that we will still make time to do nice things just the 2 of us. I wondered if anyone had any advice to help with the transition, or resources we could use/ books we could read together? I hate to think that she is feeling worried and anxious! Thanks