Disclaimer – I don't own Castle or any of the characters. Although I will admit wishing I DID own Castle after the picture of NF that was on the website from Comic-Con. He really IS ruggedly handsome!
"Zara is, uh, my little sister."
Kate stared incredulously at Rick before grabbing his elbow and dragging him out of the kitchen. "Your sister?" she repeated slowly. "You don't HAVE a sister, Rick."
Castle shrugged and glanced back at his mother and Zara through the small round window in the swinging door. "You're half right," he answered. "Richard Castle is an only child. Richard Rodgers...not so much."
Ryan poked his head cautiously through the door and poked his thumb back over his shoulder. "Hey Beckett, Martha is asking if Zara can change her sweater since it's covered in blood. Techs found her bag downstairs in the lobby."
Kate's eyes never left Rick's as she answered "Fine. Have them bag the clothes and the towel she wiped her hands on. We'll need to test for GSR."
The fire behind Castle's eyes startled her. "Are you KIDDING me?" he yelled. "Gun shot residue? You seriously think she shot Conrad?"
"Castle, I don't know what the hell to think right now," she shot back angrily. "First, you freak out when I tell you where we're going, then you take off like a bat out of hell up the stairs and I find a woman covered in blood in your arms and you're telling me she's some sister you've never bothered to mention in the four years we've worked together. Forgive me for being just a little confused."
Rick took a deep breath and ran a hand through his hair. "I'm sorry, Kate."
A crime scene tech interrupted them with Zara's bag. "She's in there," Kate said quickly. "Ryan will tell you what I need."
The tech nodded and started through the swinging door. Rick glanced in to check again on his mother and sister. "She didn't kill Conrad," Castle said after the tech disappeared into the kitchen. "No way. First of all, she has absolutely no reason to kill her father, and even if she did, did you SEE her? Why would she be that distraught?"
Kate rolled her eyes. "Guilt, maybe?"
"No," Castle said again with a furious shake of his head. Kate both loved and hated the overprotective streak that reared its head anytime she, Martha, Alexis, or now, presumably Zara, were in trouble. She appreciated his loyalty but despised how it prevented him from thinking with his head.
Rick suddenly snapped his fingers. "Cameras! Conrad had security cameras. I...I know the lobby is covered, or...at least it used to be. The stairs too, and the foyer."
He took off again for the stairs leading to the second level. "The command center for the security system was in the master bedroom closet."
"Castle!" Kate yelled after him. "We'll send the techs to take a look. YOU cannot be up there."
"What? Why not?" His face registered disbelief.
"Oh my God, Castle, conflict of interest? Your...I don't know what the hell he was to you, stepfather, is dead and your sister is, at the moment, a suspect."
Martha emerged from the kitchen looking suddenly much older than when she'd arrived and first taken Zara into her arms. "Kate, darling, is there someplace we can talk?" the older woman asked gently.
"Uh, yeah," Kate answered, somewhat startled. She stuck her head back in the kitchen and noticed Zara at the table again, clad in clean white button down shirt, sipping a cup of tea. "Esposito, I need you to keep Castle in the kitchen. Do NOT let him out of your sight."
Martha led Kate into a room opposite where Conrad Chase's body still lay in his study. It was a music room, flanked on each end by a grand piano and an ornate fireplace. Martha picked up a framed photo from a table near a small couch, glanced at it, smiled and held it to her heart before handing it to Kate.
She couldn't help but smile at the faces staring back at her. A very young Richard Rodgers and Zara Chase, sitting at the piano still in the corner of the room, with four hands on the keys, laughing as only young children can do.
"Richard was eight when Conrad and I married. Zara was barely four. Her mother had been killed in a car accident when Zara was less than a year old. Richard had always wanted a sibling and when he finally got one," Martha laughed, "he didn't waste a minute turning into a classic, stereotypical, overprotective big brother.
"They were inseparable," she sighed, gently turning the page on a music book propped against the piano. "I look around this house and I swear I can still hear their laughter. I can see them playing hide and seek."
Kate followed Martha's gaze back into the foyer, allowing herself for just a moment to imagine the young boy in the picture, with his sandy brown hair and eyes full of mischief chasing a petite blonde pigtailed little girl.
"How long were you married?" Kate inquired, snapping Martha from her memories.
"A little more than seven years," she answered. "Seven of the happiest years of my life. Well, until I caught him in his office with his secretary bent over his desk. After that, I wanted him dead."
Martha sucked in a gasp and covered her face with her hands. "I should not have said that," she said apologetically.
"Would Zara have any reason to kill her father?" Kate inquired.
Martha shook her head. "Conrad was not the easiest man to love, especially after the divorce. He tried so hard to cut me off from Zara after I sued for joint custody. She resented him for that."
"Enough to put a bullet in his head?" Kate continued.
"Absolutely NOT," Martha answered emphatically. "I've always been a part of Zara's life, thanks to some very understanding nannies."
"Rick has never mentioned her," Beckett said quietly.
Martha laughed bitterly. "That would be Conrad's doing. When he found out Richard was having a book published, he filed an injunction to prevent Richard from mentioning Zara in the acknowledgements."
"How did Castle feel about that?" Kate asked curiously.
Martha sighed. "He was angry. I was angry, so was Zara. Conrad hated to lose. It's one of the reasons he was so successful."
"Did Conrad have any enemies that you know of?"
"Of course he did. You don't get to his level of success without burning a few bridges and stepping on a few toes. You should be able to get a fairly accurate list from his assistant."
Martha took a deep breath and glanced out into the foyer before continuing. "There's something else, Kate, something the children have no idea about."