A/N: Thanks so much for the reviews! Here's chapter three.

Temperance Brennan was a rational person. Hyper-rational, some even said. She saw every human vice and could categorize it as having anthropological precedent, she could compartmentalize anything and everything in her life, no matter how minute, and she could remove herself emotionally from any situation she came across. Temperance Brennan was a rational person, because Temperance Brennan had seen everything that could possibly destroy her.

That is, she thought she had.

She thought she had, until she saw her baby lying down in his crib, covered with blood. At that moment, all rationale flew out the window, with Booth's softly uttered "Oh my god..."

"Sebastian! Sebastian, baby, wake up, look at Mama!"

She snatched her son out of his crib and clutched him to her, blood smearing all over her pyjamas. She rocked Sebastian back and forth, barely able to look at him. So much blood...

Dimly, she heard Booth calling her name, but she was so frozen in shock. Suddenly, she felt hands grip her shoulders.

"Bones, Bones, look here, listen!"

Her head snapped around to her partner as he grabbed a handful of wipes and pressed them to the limp toddler's face. Sebastian lay weakly in his mother's arms, his body still blazing with fever. Brennan heard her partner's words swell around her, still in shock.

"....blood's coming from his nose, Bones. He's having a nosebleed..."

At this, Brennan snapped to attention. A nosebleed? Her mind flashed back to the times recently where she had wiped small drops of blood from Sebastian's nose, thinking nothing more of it then the result of Sebastian wiping his nose too frequently. How could they get from there to here, with both of them sporting blood-stained clothes?

"A...a nosebleed?" she stammered.

Booth nodded, moving to take Sebastian out of Brennan's arms, but she clung tight.

"Booth, something's wrong with him," Brennan whispered, her voice trembling in fear.

"Because of the nosebleed?" Booth asked.

Brennan shook her head.

"I've seen him have nosebleeds before, in the last few weeks. He's getting new bruises every day, he refuses to eat, he's nauseous, he sleeps often, and now he has a nosebleed so bad he wakes up covered in blood." Brennan hid her face in Sebastian's soft curls, rocking them back and forth for a minute.

"He's got to go to the doctor. Something's wrong, Booth. I know it."

Booth nodded, rubbing his hand soothingly up and down Brennan's arm, before reaching over and planting a kiss on Sebastian's head and smoothing his hair.

They sat that way for several minutes, Booth stroking Sebastian's hair, Brennan rocking their son, her head resting on Booth's shoulder.

"The blood's stopped, Bones." Booth said finally.

Brennan gave a slight nod, some semblance of her usual efficient demeanour coming back. She rose from the rocking chair, Sebastian still cradled in her arms.

"Can you get some new sheets for his crib? I'll go run him a bath and clean him up."

Booth nodded and before long, Sebastian was clean, dry and ready to go back to bed. Brennan had also changed her bloodstained pyjamas.

"Mama, up." Sebastian mumbled, holding his arms up for his mother.

Brennan picked him up and cradled him against her as Booth came back. Sebastian reached out his arms for his daddy, and Booth took him and held him.

"Hey buddy, why don't you sleep in here with me and Mommy tonight, huh?"

Sebastian nodded, burying his face in his father's neck. Booth carried him over to the bed and set him down between himself and Brennan. Sebastian's mouth opened wide in a yawn, and he snuggled down into the pillow, falling asleep almost instantly.

Booth stared down at his son, stroking his cheek. A flash of worry shot through him as he took in the child's flushed cheeks. Maybe Brennan was right. Sebastian should see a doctor, if only to alleviate his partner's worrying. Parker had nosebleeds sometimes when he was a toddler, but they were never so bad for him to wake up covered in blood.

Sebastian suddenly jerked and mumbled in his sleep. His eyes opened a slit, then closed again. Booth looked up at Brennan.

"Cyclonic jerks," Brennan explained sleepily, snuggling down into her pillow. "Caused by the sudden contraction of the muscles when falling asleep. It has been theorized that it's caused when respiration rate falls in preparation for sleep, and the brain interprets the signals as the body dying, causing the muscles to contract in order to jerk the body awake."

Booth stared at her for several seconds.

"What?" she mumbled.

Booth shook his head and smiled. He reached out his head and stroked his partner's hair. She smiled and placed her hand over his.

"He'll be okay, right Booth?" she asked, uncertainty creeping into her voice. Booth smiled.

"He is his mother's son, Bones," he replied, getting a smile out of her. "Like you always say, we won't worry until we have to."

Brennan nodded, still unsure but slightly reassured. Looking down at her sleeping son, she brushed a hand over his head. The scientist in her was telling her that Booth was right, that jumping to any conclusions would be irrational and presumptuous.

But the mother in her made her lift her son onto her chest and cuddle him close, whispering softly into his ear.

"It's going to be okay, baby. Mama's not going to let anything happen to you, I promise."

A/N: You know you want to review. You know the button is just begging to be pushed. I'm sure there's an anthropological precedent in review pushing, so you really shouldn't fight it.