Random X reader

Not so secret santa (BBC sherlock x reader)

"Merry Christmas sweetheart," you said waking up your some William.
"Morning mommy," he said getting out of bed.
"Santa came last night," you said with a big smile.
William ran out of his room and stopped when he saw all of the presents under the tree. Your heart melted when you saw your son's eyes widen with joy.
"Merry Christmas," your husband, Sherlock said wrapping his arms around you from behind.
"Merry Christmas Sherlock," you said turning around kissing him.
"Awesome a next chemistry set. Now I can help daddy," William said excitingly.
You went to grab your camera and Sherlock when to sit by his son.
"Look dad it's just like your," William said showing his father.
"It is buddy," Sherlock said patting his back.
"Go see what else Santa got you," you said sitting next you your son.
William finished opening his presents and you went to get breakfast ready.
"Dad," William asked his father.
"Yea buddy," Sherlock asked.
"Does mom know Santa isn't real," he asked.
"What do you mean. Santa is real," Sherlock said thinking about his conversation with is wife.
~flashback~
"I swear Sherlock you better not ruin Christmas," you said making Williams lunch.
"It's impossible for one man to give every child in the world presents in one night," Sherlock said.
"It's every good boy and girl," you told him.
"Still that's way to many in on night," he said.
"It's called magic," you said packing it in Williams back pack.
"(Y/n) there is no such thing as magic."
"Why must you ruin Christmas with your stupid logics. It's for the children."
"Yes let's let them believe in a man who breaks into their house. Eats cookies and drinks milks. Leaves present if you are good and coal if you are bad."
"I swear Sherlock if you tell William Santa isn't real. You will be rooming with John again," you said grabbing William's bag and bringing it to him in the living room.
~flashback over~
"Santa is real," Sherlock said.
"Dad, some of the tape has the same (f/c) nail polish she always wear. And all of the hand written is either your or mom's," William said.
Sherlock looked behind him to make sure his wife was not in hearing distance.
"Son, you mother wants you to believe in Santa Claus," Sherlock said.
"But it's impossible for him to travel around the world in one night. And to visit every good girl and boy. Plus how would he know who is good and bad," William said.
"I know son but for your mother present to believe," Sherlock said.
"Can I help you and uncle John on your next case," William asked.
"You are going to even if I say no am I right," he asked.
"Yes," William said getting up and running into the kitchen.
Sherlock got up and followed his son into the kitchen.
"Mommy can I write a letter to Santa to thank him please," your black haired boy and (e/c) son asked.
"Sure," you said grabbing him paper and pen.
Sherlock walked behind you and wrapped his arms around you.
"Thank you," you said turning around.
"Your welcome," he said looking down at you.