Yesterday, a dad called Christopher Hope-Smith put up a small request on Twitter.
Hope-Smith, from Leeds, explained his eight-year-old son Ollie was about to celebrate his ninth birthday on 5 July but that he was currently going through a tough time at school.
Hope-Smith's tweet has now been shared almost 10,000 times. And a whole range of people, including celebrities, responded. Here's Stormzy's message:
Australian actor Russell Crowe:
Astronaut Tim Peake:
Strictly Come Dancing champion and presenter Ore Oduba.
Presenters Sara Cox and Jake Humphrey both recorded messages for Ollie's birthday:
PENNY FROM FIREMAN SAM!
The pair later sent Ollie a birthday message:
We hear it's your birthday – the big 9 – have a great day from Rob Lee and his pal Fireman Sam in Pontypandy. X"
THE ENGLAND FOOTBALL TEAM!!!!
AND THE CLANGERS!!!
After *all* the attention, Hope-Smith's wife posted late last night.
"I don't 'tweet' and always go on at him for spending too much time on Twitter!! However, this time I am completely overwhelmed by everyones kind thoughts," she wrote on his account.
"You do not know what this means to me and will to Ollie when we show him. I have been battling with this matter for over a year and am only just now being listened to.
"It is heartbreaking listening to an 8-year-old think that he is worthless and 'shouldn't be here'. I know that we are definitely not the only ones in the world to be going through this but I just want to say, from the bottom of my heart 'Thank You' so much. You really don't know what this means, Natalie xx".
Hope-Smith posted thanking everyone for their messages, and explaining he had no idea it would go so far.
And he had one important thing to say:
So happy birthday, Ollie! Have a great day!
Christopher Hope-Smith has been contacted for comment.
Rose Troup Buchanan is a reporter for BuzzFeed News and is based in London.
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