Delaney posted on Facebook Saturday morning saying that doctors discovered the brain tumor shortly after his son's first birthday, which was removed and treated in early 2017.
'I don't want to miss out on their handsome lives.
Delaney writes, "Henry was a joy".
He passed away in January and Rob thanked the NHS for looking after his son and praised his wife Leah and Henry's two older brothers who are six and five for staying strong.
I have very sad news.
"They are why I will endeavor not to go mad with grief", he said.
"He was smart, funny, and mischievous and we had so many wonderful adventures together, particularly after he'd moved home following fifteen months living in hospitals", he added. "I'm voracious for more encounters with them".
He said: "I'm insane about London, I love it so much".More news: Sexy shirtless Tongan hunk Pita Taufatofua grabs Olympic attention again
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Delaney likewise shared where individuals can give to help different families with kids who are extremely wiped out.
Rob, who is from MA but now lives in London, thanked the NHS nurses and doctors, as well as the charity workers and home care people that helped them during the hard illness, saying they "will be my heroes until the day I die".
"Rob, my heart is broken for you and your family".
"Our family would be fit as a fiddle at the present time if not for them". I would also urge you to take concrete and sustained action to support the NHS, however you can. "Try not to underestimate it". He asked people to respect his family's privacy in this hard time and signed off by saying, "Thank you, handsome Henry, for spending as much time with us as you did. We miss you to such an extent".
He at that point told perusers, "At last, I ask that you regard my family's security with respect to this issue".
"In the United States of America you could be denied healthcare if you have a pre-existing condition, which can literally include "has had a child", Delaney told the Radio Times.
Our musings go out to Delaney and his family as of now.