It seems Robert Downey Jr is a man of his word.
Six months ago, the Iron Man actor hopped into action when Vicky Keyte contacted him to say her young son Daniel, who suffers from cystic fibrosis, was not feeling well.
The actor dressed as Tigger and posed for a photo, writing: "When I'm in the dumps, I've found this little getup to be helpful. P.S. Would you like to come to the LA premiere of Captain America: Civil War as my guest? If so, have your people call my people. All the best."
But it was at the European premiere in London on Tuesday night that Daniel got the chance to meet his idol.
Alongside a picture of her son and Robert, Vicky posted on Instagram: "It's happened!!!"
Earlier in the day, she shared an image of the car sent to collect Daniel, writing: "And so it begins! Daniels big day is finally here and so is surprise number one, Daniels own personal driver in a beautiful car."
Daniel was not the only child to receive a special premiere invite from Iron Man himself.
Ethan Miller, who met Robert on Monday at Great Ormond Street Hospital and posed for photos wearing his Iron Man costume, also received an invite.
The seven-year-old suffers from the rare blood disease ITP, as well as type 1 diabetes.
He seems to have formed a firm friendship with Robert - as the two were pictured deep in conversation.