Mycroft heard his little brother's cries from next door and immediately jumped out of bed, walking into Sherlock's room without knocking.
"Mycroft?" The little boy whispered, sitting up as he heard the approaching footsteps.
"Yes, Sher, it's me." Mycroft replied softly, sitting down on the bed.
"I'm sorry for waking you, My."
"It's alright, dear brother. Was it the storm?"
Sherlock nodded slightly, his eyes red and puffy from crying.
"Come here." Mycroft said gently, lying down on the bed and pulling Sherlock to his chest.
"Will you stay?" Sherlock whispered, snivelling slightly.
"Of course." Mycroft smiled softly, kissing his little brother's curls.
"Thank you." Sherlock replied, jumping when another flash of lightning lit up the room.
"It's alright, Sher. I'm here."
Mycroft stroked Sherlock's curls softly, whispering nonsense in his little brother's ear to soothe him.
"I miss Mummy." Sherlock whispered, interrupting the silence.
"As do I, dear brother." Mycroft whispered back, holding Sherlock tighter.
"You're staying, right?" Sherlock asked softly, snuggling further into his brother's chest.
"Of course I am, Sher. I just ..."
"I mean even when the storm ends."
"Yes, I'll always be here, little brother."
"Thank you, My."
"You're welcome, Sher." Mycroft replied softly, kissing his brother's curls again.
Sherlock hummed softly before going limp in Mycroft's arms and falling to sleep.
"I'll always be around, Sherlock. I promise." Mycroft whispered to his sleeping brother, breathing in his scent. "I love you, dear brother."
"Luv you too, My." Sherlock mumbled softly, snuggling further down under the covers.
Mycroft smiled sweetly, letting himself drift off into a peaceful sleep.