Image caption Christine Mackie (left) has written the play, and daughter Lois will star

Christine Mackie, best known for playing Coronation Street's genial GP Dr Gaddas, has written her first play at the age of 62, inspired by the suicide of her father, and starring her daughter.

Christine was 11 when her dad, a Second World War veteran, took his own life. He had bottled up the ordeal of war and the depression that followed.

That was 1968, and his death was a trauma that the young Christine couldn't process at the time. She too bottled her feelings up.

"Nobody talked about anything," says the actress, who is also known as Downton Abbey's Mrs Bryant. "We just got on and went back to school, went back to work, got on with things. I didn't cry because if I cried it upset mum. If she cried, it upset me. So we didn't cry. I didn't really want to deal with anything until I was about 14, and I went a bit loopy."

Image copyright Mark Bruce/ITV Image caption Christine Mackie (left) as Dr Gaddas in Coronation Street

For the next three decades, she largely kept her memories and feelings about her father shut away. It wasn't until she was in her 40s that she finally worked through her grief.

By that time, she had two young daughters. She sought professional help - not initially for herself, but to take advice about how to talk to her girls, worried that they might somehow feel suicide was something that could follow the family.

Her GP referred her to a grief counsellor. "And it was absolutely transformative for me," she says. "She gave me back my dad. Because in a way, since his death, it was almost like he hadn't been there. Because we didn't talk about him."

Now, she has written a one-woman play inspired by the grief caused by the loss of her father and the transformational effects of therapy. It's not a direct retelling of her story - it's set in the present-day and the central character is younger than Christine herself was when she sought help. The character is played by Christine's daughter Lois.

"We've been approaching it in quite a detached way, in the sense that we're trying not to remember that it's this huge personal thing," Lois says. "That it isn't my grandfather, that it is a character and a job that I'm doing. Keeping it like that has helped a lot."

Image copyright Christine Mackie Image caption Christine Mackie's father Harry took his life at the age of 45

Christine's father - Lois's grandfather - escaped from a prisoner of war camp in Italy and was hidden by a local family who, she says, would disguise him as an old lady when the army came to the village. "He was a long time coming home, and when he got back, everybody had got used to him being dead," Christine says. "His fiancé had married somebody else and didn't expect him to come home."

In the play, titled Best Girl, the father figure is a Gulf War veteran. Lois's character is called Annie, who has relationship problems that stem from the damage caused when he took his life. It becomes hard to trust anyone after a tragedy like that befalls you at a young age, Christine says.

"Even though you are functioning, it's very hard to make relationships. It's very hard to believe that anybody is going to stick around for you. 'Why would you stick around for me when you just met me, when my dad didn't stick around for me?' So that's a time bomb you're dealing with, even if you're still managing to go to the shops and go to school and work and all the rest of it."

Thankful for her therapy, she describes the play as "a love letter to the NHS", and the fictional Annie is allowed to get professional help earlier than Christine was able to in real life. "I think it is wonderful that Annie makes this discovery and has the chance to be liberated while she's still so young," Christine says.

Image caption Christine Mackie (right) played Penelope Wallace in the BBC's Doctors in 2016

As Dr Gaddas, Christine's consultations have included treating Coronation Street's Steve Macdonald for depression. It's fitting that the actress's debut script is an homage to the medical profession. "She would be very thrilled. She's also quite often in scenes wanting people to talk. This is my fifth year being Dr Gaddas, which is a tremendous joy to me. I love going there."

She films on the cobbles about once a month, popping up whenever one of the Weatherfield residents needs to see their friendly local doctor. She has a trick to making Dr Gaddas slot in seamlessly - imagining that she is actually the star of her own parallel soap opera.

"Whenever I go in, I know very well my place. The scene is not about Gaddas, it's about somebody else. So in my little head, I have my own soap opera where I'm really busy and I just want to get this scene over so that I can just get on and do something.

"So that's my energy when I go in, 'Oh, that's very interesting, but you know, there are things I've got to do'. Then something will happen and I'll go, 'OK, tell me more about it'. I like that. It makes me laugh."

Best Girl will be performed at the Greater Manchester Fringe before a run at the Edinburgh Fringe. Christine and Lois are giving a portion of the ticket sales to two mental health charities - FirstLight Trust and Young Minds.

Young Minds provides and campaigns for mental health support for children and young people. The charity's campaigns director Tom Madders said: "Losing a parent to suicide can be extremely difficult to make sense of for any child or young person.

"There is no right or wrong way to grieve - what's normal for one person may not be for someone else - but talking to someone you trust, like a friend, a family member, GP or counsellor, can make a real difference. Grief doesn't have a timeline, so be patient with yourself. Remember you don't have to deal with this alone."

Meanwhile, FirstLight Trust helps war veterans. Christine Mackie recently visited one of its cafes, where former servicemen and women can go to talk. "I was looking at these guys chatting and thought, who did my dad chat to?" she says.

"Who did my dad talk to, really? Nobody."

Best Girl is at Hope Aria House in Manchester from 18-20 July and at the Pleasance Courtyard in Edinburgh from 31 July-26 August.

If you would like support, you can phone The Samaritans on 116 123 or email jo@samaritans.org. Calm can be contacted on 0800 58 58 58 (17:00-midnight). Details of other organisations that can help are on the BBC Action Line website.

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