Harington, 35, played Jon Snow in HBO’s massively popular fantasy series Game Of Thrones, which ended in 2019 after eight seasons.
The London-born star and actress Leslie, 35, who is from Aberdeenshire, met while starring together in the TV series, and tied the knot in 2018 at her ancestral castle in Aberdeenshire.
The couple, who have a home in Edinburgh, had a son, whose name they have not released publicly, in early 2021, with Leslie telling Harper’s Bazaar UK: “He (Kit) wore the BabyBjorn (baby carrier) loud and proud.
“And there were many satisfying moments; we had an understanding that, when our son cried in the middle of the night, it was on Kit to go and look after him, as I would have to wake up early to work – it was kind of glorious.”
She will next be seen in six-episode series The Time Traveler’s Wife, based on the 2003 novel by Audrey Niffenegger and adapted for the small screen by former Doctor Who showrunner Steven Moffat.
The series, due to air on Sky Atlantic and streaming service Now in May, sees Leslie play Clare Abshire, the wife of Henry DeTamble (Theo James), a man who, due to a genetic disorder, time travels – often unexpectedly.
The 2009 film version of the book starred Eric Bana, Rachel McAdams and Ron Livingston.
Leslie, who features on the cover of Harper’s Bazaar UK’s June issue, spoke about filming as a new mother, telling the magazine: “I remember finding it very brutal, being wrenched away from him.
“There were parts of me that doubted whether I would be able to see it through for six months. It was so tough.”
Harington overcame problems with alcohol and depression following the end of Game Of Thrones and said earlier this year, in an interview with The Guardian, that he was “so grateful” he got sober before he and Leslie had a baby.
Of her husband’s past struggles with addiction, Leslie told the publication: “I’ve learnt a lot about addiction and it’s something Kit is forever going to be aware of, but it’s on him whether he chooses to drink again.
“No amount of nannying is going to be able to stop him from doing what he decides to do… I don’t choose to put that pressure on myself.
“The responsibility of his behaviour is on him. It’s not on me to guard him from it.”
The June issue of Harper’s Bazaar UK is on sale from May 4.