Has a letter arrived for me?

“Has a letter arrived for me?” Billy sat on the third stair from the bottom, drumming his little hands on his Spider-Man pyjama bottoms. “Dad!”

“What?” grumbled dad as he continued to flick through the post, deliberately flicking past anything that looked like it contained any information about money owed, which as ever, was nearly everything that he'd picked up from the floor that morning.

“Has a letter arrived for me, dad?” Billy repeated, as he slid down the remaining stairs on his bottom. Dad turned round, “WALK down the stairs” he growled, before adding, “your mum is in the kitchen, go and get your breakfast”. Billy thought for a second about asking once more, but instead flopped his arms to his side and dragged his feet, squeaking along the cheap laminated floor.

“Morning, sunshine”. Dad turned back to the envelope marked Billy Brown, 19 Stadium Way, London as mum greeted Billy in the kitchen. He positioned himself on the third step of the stairs, slid his thumb under the crease of the envelope and quietly started to tear it open. ”How's my big boy? 4 today!” exclaimed mum, as the sound of coco pops tumbling into a bowl masked the final rip of the envelope.

Dad slid the card out and opened it up. “Bingo” he whispered, as he removed the crisp twenty pound note out from between the folds.
As he attempted to place it back within the now tatty paper envelope, he looked at the front of the card.

To my son, on your birthday…

He pushed it back in and stood up, his knees cracking as he did.
“Hey, Billy, your letter arrived”.