There She Goes - the comedy drama following the life of Rosie Yates (Miley Locke), a severely learning-disabled girl and her family, dad Simon (David Tennant), mum Emily (Jessica Hynes) and older brother Ben (Edan Hayhurst) - is back for a one-off special. Rosie is now 13 in this special, and is starting to display increasingly challenging, emotional and physical behaviour.

Below, the four key cast members talk about returning to the show, and following that chat we have a Q&A with writers Shaun Pye and Sarah Crawford, who have based the show on the real-life experiences of their daughter.

Can you tell us what's in store for the Yates family in this special?

David: They get some long-awaited information on Rosie's condition, but getting some answers doesn't necessarily give them the closure they imagined it might.

Jessica: There's big changes for everyone as Ben and Rosie are growing up and Simon and Emily are coming to terms with what that might mean for them all. Dealing in real time with finally getting a definitive diagnosis of Rosie's condition and the rollercoaster of emotions it brings. There's also flashbacks to the moment Emily and Simon considered having a third - how the pros and cons were not what they expected and how ultimately making that decision together brought them closer.

Miley, what was it like becoming Rosie again?

Miley: Becoming Rosie again was so lovely. I have played her from a very young age and being able to play her again was fun, emotional but overall, the most incredible experience and I'm so grateful I got to do this again.

What research did you do to prepare for the role?

Miley: I've meet Joey, who Rosie is based on, lots of times. Shaun sends me lots of videos of her and he gives me lots of advice on how Joey would be in each scene, we work on it together. Sarah also helps give me direction along the way.

What was it like reuniting?

David: A real pleasure.

Edan: It was lovely to see everyone again, they are a talented crew and very funny! I enjoyed catching up after what feels to me like ages and I felt I had a lot to learn from them, especially this time round.

Miley: It was great being with the cast again as we all get along so well and have so much fun together, it's like being with family. They are so easy to work with, so it was a pleasure to be able to see them all again and play our characters together.

Jessica: Miley and Edan are still a complete delight - growing into fine accomplished young actors, it was wonderful to see them again. David was, as always brilliant, effortless and joyful to work with.

We see Simon practically having to wrestle Rosie back into the house. What was it like filming those scenes with Miley?

David: Miley continues to be incredible as Rosie. She has been right at the heart of this story from our first day on set and we wouldn't have been able to tell this story without her.

Simon and Emily make a number of cult references throughout the two series and the special. Are there any that are particularly memorable?

Jessica: I can't remember any, which proves I am a fraudulent nerd.

David: The debate over what the correct plural for Batman is has stayed with me and is something I often find myself pondering.

Ben has some pretty tense moments with his father. What was it like filming those scenes Edan?

Edan: It was quite tense, the atmosphere on set definitely changes relative to the scene and it's all supported very nicely by the cast and crew. David is very easy to work with - he's effortlessly funny and you can't help but get on with the guy and that comfortable space is needed to really delve into the emotional parts of acting. It's hard to find that when you don't feel so at ease in your work. I found him easy to act off of and that's all you can really want.

Jessica, did you bring any of your own parenting experiences to the role?

Jessica: Instinctively yes, I think so. Rosie bashes a soup spoon out of my hand in the scene and I picked it up, put it in my mouth to clean it quickly and then offered her the soup again (which she doesn't take) - that is a reflex from being a mum and spoon feeding toddlers.

Have you received messages from parents in similar situations to Simon and Emily?

David: I know that There She Goes has connected with a lot of families who see their own situation reflected on screen in a way they've never seen before.

Jessica: I'm not on any social media, so no, but I have had letters of congratulations and requests to be part of Learning-Disabled charities which is a great honour.

Edan: I am proud of the project and proud to be a part of something so poignant and inspiring in its topic. The script was very compelling and sometimes quite dark but the series carries it well with its humour. I enjoyed seeing it come together, in the end it felt like a heart-warming show and something I felt very grateful to be a part of.

Miley: The reaction to the series has been so positive, a lot of families have reached out to me and said this is very similar to their family life, and that they haven't seen anything like this before on TV, and that makes me very proud to part of the show.

What is it about Shaun and Sarah's writing that makes this show appeal to you?

David: Their honesty. They tell their story with absolute candidness and humility and humanity.

Jessica: To work with artists like Shaun and Sarah has been one of the privileges of my career. I am in in awe of their bravery, honesty, humour and skill in creating this important family story with flawed, funny, truthful characters. Also, they give me lots of lines, which I like.

Do you have a favourite scene you enjoyed filming?

Miley: There's a scene where I kick tomato soup over Jessica and David which was great fun to film; the soup landed everywhere it wasn't meant to. There were a lot of laughs in between takes.

What do you think viewers will take away from the special?

Jessica: That life is a crazy, amazing, random gift that will only ever make sense if you always lead with love.

Miley: I hope viewers enjoy seeing the next chapter in Rosie's life and take away the love, laughter and tears we all share in the Yates family.

David: Telling Rosie's story has been a labour of love for everyone who has worked on it but particularly, of course, for Shaun, Sarah, Frank and Joey. I'm very proud to have been part of it and I hope as many people as possible will see it, and perhaps go back and discover Series 1 and 2 if they haven't already. It's been a truly special project.

Writers Q&A: Shaun Pye and Sarah Crawford

Why did you want to tell Rosie's story?

Joey Pye is an extraordinary young woman - funny, infuriating, adorable, irritating, inspiring, heart-breaking - and a character we've never seen portrayed on television.

The chromosomal disorder community is hidden away in mainstream culture. As Emily says in the show: "Nobody dreams of a child like Rosie". We wanted to create a show that was first and foremost a funny and emotionally captivating piece of telly. But we also wanted to show what life with a learning-disabled child with a chromosomal disorder was really like.

What sort of reaction have you both had about the show?

Astonishing, really. A huge number of families with experience of chromosomal disorder have contacted us to say they've finally seen a true depiction of their life on telly - the most common comment is that the show "gets it".

Did the rest of the family have any input into the writing of the show?

Yes. On one level the show is really written by Joey. As everything in it is based on real events Joey generates almost all the situations and inspires the words. For this episode our son Frank has also contributed a lot - not just with his alter ego, Ben, but with story, character and dialogue.

What advice would you give to parents in a similar situation to the Yates?

Firstly, I'd tell them that they're doing a hard job very well. There's a scene in the episode when a stranger tells Emily that she's doing a good job and all the mums are proud of her. This, like everything in the show, is based on a real incident. Those few words meant a lot. Because sometimes it can feel like you're failing at this - you're not. It's okay to hate the situation life has dealt you, it's normal. It's fine and you've got this.

The second bit of advice I'd give is to seek out the charities and support groups. The forum we're members of is one of the most useful and supportive communities you could ask for. If you're having a hard time, if there's something worrying you - someone has been there before. You're not alone.

How would you describe There She Goes to someone who might not have seen the show before?

A funny and at times very emotional story of an extraordinary and unusual little girl told with absolutely unflinching honesty.