This might become a multi-chapter story later on, but for right now it's a One-shot. This is also my first time writing anything for either Doctor Who or Sherlock so I apologize in advance if it sucks. XD
As is my custom I will post a disclaimer: I do not own any characters or settings in this story. They are the property of BBC.
The wheezing, groaning sound of the TARDIS echoed across the small park as it materialized in the murky darkness. Inside, the Doctor flipped the final switch on the console and leaned against it with a disheartened sigh. He crossed an arm over his chest an rubbed his forehead with his other hand; unsure if he was ready for this.
A soft melodic tune floated up from somewhere in the TARDIS and the Doctor pushed himself off the console and followed it. He reached a small room with walls painted to look like the night sky. A small device made it appear as though thousands of stars shone in the little room. And standing amid the softly glowing sky-scape was the source of the melody. River was humming a lullaby. She stopped humming long enough to whisper "Hello Sweetie" before starting up again, a sad note creeping into her voice.
The Doctor walked up beside her, resting his hand at the base of her neck, amid her voluptuous curls. He kissed her temple and she turned to smile at him, but it never reached her eyes.
"How's he doing?" He asked and River's smile dropped slightly, but a tender warmth filled her eyes. They both looked down at the small bundle she was cradling. A round face peeked out at them from inside the blankets, a single dark curl falling into his forehead. Bright bluish-gold eyes stared up at them with a knowing no child should possess.
"He loves looking at the stars." She responded, motioning at the room with one hand. She softly caressed the babies cheek and he pulled a hand from the blankets to grab her thumb. She then lowered her head and gave him a kiss on his forehead. He quickly let go of her thumb and wrapped his fingers in her hair. Not wanting to break his tenuous grip, she scooted him up higher in her arms. "I don't know if I can do this."
The Doctor noticed a tear slide down her cheek and started. He wasn't sure how to deal with this vulnerable person in front of him. He was used to a strong, fiery woman, the sassy, flirty, kill-you-if-you-wrong-me, woman. It broke his hearts, seeing her like this. And dammit if he wasn't close to tears himself. It felt wrong, what they were about to do; necessary, but wrong. "We have to, you know that. We've waited too long as it is." He squeezed her shoulder, trying to sooth her. "I hate it as much as you do, but we have to think about what is best for him. For our son."
"Our son." River echoed, hugging the baby to her. The Doctor hugged her shoulder, wishing he could make it better. River let him hold her for awhile, content in his arms, but knew they were just procrastinating. If they didn't do this now, they never would, so River straightened her shoulders and cleared the lump from her throat. "Come on Sweetie, she'll be waiting."
Side by side they made their way back to the console room. The Doctor walked with his arm around his wife's waist and River cradled their six month old son in her arms. As they stepped through the control room, River ran her free hand over the console and the TARDIS hummed back reassuringly. They lingered there a moment, but knew there was no delaying the inevitable. So with a sigh, the Doctor opened the doors and he and River stepped out of the TARDIS.
They left the small park and walked down the lane to a house with a well-kept garden and low rock wall. Pausing long enough to glance at each other, they stepped passed the gate and walked up the path to the front door. The Doctor knocked and River repositioned the baby so she could grab his hand.
A woman with dusky blonde hair and bright blue eyes answered the door. She gave them a warm smile that they returned it with stiff ones of their own. "You must be Doctor and Mrs. Song. Please come in."
"Actually." River said, glancing at the infant in her arms. "It would be better if we didn't."
"I understand." She acknowledged, stepping out of the doorway. "This must be very hard for you."
"It doesn't get any easier." The Doctor mumbled. The lady gave him a puzzled look, but River gave his hand a reassuring squeeze.
"Are you two absolutely sure about this?"
"Yes." River answered, steel in her voice. "It must be done."
"But to give up your child?" The lady asked, wanting to make absolutely sure they thought it through.
"It is what is best for him." The Doctor said, trying to hold it together. "Our lives are far from peaceful. The dangers we must face are too great to raise a child amidst it all. This is the only way to keep him safe."
"What about this perception thing? What is it for?" The lady asked, moving on.
"The perception filter, which is just a small chip in the back of the neck, is to keep others from finding out he is different from ordinary humans. It would seem as though he has only one heartbeat, his blood would appear normal, and his Time Lord consciousness will be hidden. Not even he will know any of this." The Doctor looked at River and nodded. She returned his gesture, kissed her son's forehead, then hugged him close. The Doctor threw his arms around the both of them and they stood embracing. Then he let go of them and took the baby from River.
"I have been alive for a very long time." The Doctor sniffled, openly crying. "I have done some pretty amazing things, and seen more than I care to remember, but you, Sherlock Williams-Song, are the single greatest achievement I have ever accomplished. You are my proudest moment. I love you with all my hearts."
He hugged him close, whispering to him in Gallifreyan. When he finished he stepped closer to the woman. "Your son, Mrs. Holmes. Give him the life we never could."
Mrs. Holmes cradled Sherlock in her arms, a tear falling down her cheek. "He's precious. I will love him like my own." She laughed then, a small chuckle of released tension. "He will be spoiled before the weeks out. Mycroft, my boy, has been saying for years he wanted a little brother, and my husband has always wanted a son to take to go see a match. Mycroft detests sports. Oh listen to me, I'm rambling."
They heard the far off groan of the TARDIS and knew she was saying: "Time to go." They made their excuses, kissed their son goodbye for the last time, then left. It wasn't until they were back in the TARDIS, flying through the Time Vortex, that they allowed themselves to break down completely.
They had done what no parent should ever have to do. But by doing so, they gave their son the opportunity for a safe and happy life.