The daughter of Isis beheading victim Alan Henning found out about his execution by seeing photos on social media, she has said.
Lucy Henning, 18, had hoped the terror group would release her father until she came across the gruesome pictures on Instagram.
Her father, a 47-year-old taxi driver from Salford, had gone to Syria to help deliver aid after being deeply affected by the plight of orphan children in the war-torn country.
But he was kidnapped after going over the border from Turkey in December 2013 and held hostage by Isis for 10 months.
Despite worldwide appeals and calls for mercy by his family the terror group released a video in October last year, of him kneeling in an orange jump-suit in the desert as he was beheaded.
Miss Henning, speaking on The Jeremy Kyle Show, titled 'My dad was executed by ISIS' broadcast later today on ITV, said: "I remember thinking we have had a few days, no news, it's looking good. We thought they might actually let him go.
"Then I remember I was just laying in bed on Instagram and er, I just saw the final picture. It was the final picture, after the execution.
"You just kind of go through in your head, like whenever I used to get upset about it, I used to torture myself thinking, 'You don't know what he's going through,' so how can you sit there crying.
"So I used to just shout at myself, you can't cry, you can't be upset, think about what he's going through, think about what everybody else is going through."
Miss Henning said she is still trying to come to terms with her father's brutal murder at the hands of Isis.
She added: "I try not to think about them. I think I'm still numb. I just try and get everyone to remember like, the kids that are still there, when people say, 'Oh you've lost your dad,' Yeah I know but there's kids there that's lost, lose all their family in one day and they are stuck there on their own."
Miss Henning said she is herself looking to do voluntary work in Africa and hopes to make a visit in memory of her father to the region.
"There's an academy that's been set up in my dad's name, the Alan Henning Academy, for Syrian children, just on the Turkey side, and it's schooling around 400 pupils at the moment, getting them the education they need, so I would like to go and visit," she added.
More information can be found at: http://www.u4h.org.uk/project/the-alan-henning-academy-2014/