I was watching 'Twilight, Breaking Dawn Part 2' when this idea popped into my head. ' Let me know what you guys think.

Clary, Alec, Magnus, Simon, Izzy, Maryse & Luke were all gathered in the Institutes' Music room watching as Jace taught his and Clary's daughter, Celine how to play the piano. She picked it up quickly much to the amazement of the adults around her. Celine was a talented child not only with her training but in the creative arts. She had inherited Clary's impeccable artistic skills and Jace's musical talents. Not only had she inherited their talents but she had also inherited their looks, she had Clary's fiery red hair and Jace's stunning golden eyes.

Clary was watching her daughter and husband with a smile on her face when her world became blurry and the sound of her daughter playing the piano became distant. Their were flashes in Clary's mind. Fire and screaming, two crowns and thrones. Then it all became clear the three faces that formed in her mind caused her gasp. Bringing herself back into the present she stumbled back, knocking into the bookcase behind her. Her actions caused the piano to stop abruptly and every face in the room turned her direction. Jace instantly stood up and he looked in concern at his wife.

J-"Clary?

M-"Biscuit? You okay?"

C-"Yeah. I'm fine. I just realised I need to check something."

Clary started to exit the room but was stopped in her tracks by Celine running up to her and hugging her tightly. Clary hugged her daughter back before Celine pulled away and looked up at her mom with a small smile.

CE-"Feel better, Mommy?"

C-"Yes thank you. Now go back to daddy, mommy won't be long."

Celine lets go of her mom's waist and runs back to the piano where Jace is watching in concern. Clary takes a deep breath and walks out of the room, Magnus and Izzy share a look with each other before following, leaving the music room in confusion and concern.

Being Clary's parabati, Izzy knew when something was wrong and she could tell, as she led Magnus to the library, that Clary had become increasingly panicked about something. They entered the library to find Clary pacing by a round table.

I-"Clary?"

Clary stopped and turned to the two as Magnus shut the door behind them.

C-"Izzy, Magnus what are you doing here?

I-"I'm your parabati, I know something's wrong. So spill, what's happened?"

Clary takes a deep breath and lets it go before speaking,

C-"I had a vision."

M-"You haven't had one of them for years."

C-"I know, this one was not like the others. Their was no runes. It was just images. It was a warning."

I-"A warning for what?"

Clary takes another deep breath before continuing.

C-"Lucifer, Lilith and Johnathan are coming for Celine."

I-"What! Why?"

C-"I don't know?"

M-"I think I do."

The duo looked at he High Warlock of Alicante, as he walked towards them.

M-"Celine is Clary and Jace's daughter and a Shadowhunter. But what is special about her is that she is the daughter if two subjects of Valentine's experiments, meaning..."

C-"She has angel blood in her system."

M-"Exactly, When you and Jace are separate, you are strong but together, you're unstoppable."

Clary sinks into the seat behind her, Isabelle not far behind her as Magnus explains his theory.

LATER THAT NIGHT

Clary was tucking Celine into bed,

C-"All snuggled up?"

CE-"Yes, Mommy can you sing me to sleep?"

C-"Of course I can."

You fascinated me

Cloaked in shadows and secrecy

The beauty of a broken angel

I ventured carefully

Afraid of what you thought I'd be

But pretty soon I was entangled

You take me by the hand

I question who I am

Teach me how to fight

I'll show you how to win

You're my mortal flaw

And I'm your fatal sin

Let me feel the sting

The pain

The burn

Under my skin

Put me to the test

I'll prove that I'm strong

Won't let myself believe

That what we feel is wrong

I finally see what

You knew was inside me

All along

That behind this soft exterior

Lies a warrior

My memory refused

To separate the lies from truth

And search the past

My mind created

I kept on pushing through

Standing resolute which you

In equal measure

Loved and hated

You take me by the hand

I'm seeing who I am

Teach me how to fight

I'll show you how to win

You're my mortal flaw

And I'm your fatal sin

Let me feel the sting

The pain

The burn

Under my skin

Put me to the test

I'll prove that I'm strong

Won't let myself believe

That what we feel is wrong

I finally see what

You knew was inside me

All along

That behind this soft exterior

Lies a warrior

Lies a warrior

You take me by the hand

I'm sure of who I am

Teach me how to fight

I'll show you how to win

You're my mortal flaw

And I'm your fatal sin

Let me feel the sting

The pain

The burn

Under my skin

Put me to the test

I'll prove that I'm strong

Won't let myself believe

That what we feel is wrong

I finally see what

You knew was inside me

All along

That behind this soft exterior

Lies a warrior

The pictures come to life

Wake in the dead of night

Open my eyes

I must be dreaming

Clutch my pillow tight

Brace myself for the fight

I've heard that seeing

Is believing

Celine had fallen fast asleep by the time Clary had finished the song, so Clary carefully climbed out of the bed turned off the lights and left the bedroom. She made her way quickly to Izzy's office where the rest of the group were waiting. Clary entered, all eyes made their way to her as she shut the door and stood next to Izzy.

I-"Okay?"

Clary nodded her head and looked to Magnus to continue.

M-"Celine is not just a Shadowhunter. She's the daughter of Jace and Clary, now to outsiders that might not seem like much but to us and every shadowhunter, downworlder and angel that's the biggest threat."

S-"Why?"

C-"Jace and I both have angel blood in our veins from Valentine's experiments. Celine has more angel blood in her system than either one of us because she is us, combined."

L-"But that doesn't explain why the King and Queen of hell and Clary's dead brother are coming for her."

M-"Actually it does. You see Celine is the only child in the world with angel blood in her veins, not only that she is probably the most trained and skilful shadowhunter yet."

The room is in a silence as the adults digest this information. Jace walks over to Clary as he can notice how uncomfortable she is. He places an arm around her waist allowing her to be standing against him.

I-" Their's more."

A-" More?"

I-"Because of the angel blood in her system she..."

Izzy trails off as she looks at Magnus and Clary before Alec's voice snaps her out out of it.

A-"She what?"

I-"She has a claim to the throne of hell."

The room goes into a heavy silence again, nobody knowing what to say or do. After a while people started to head home. Maryse, Luke, Magnus and Alec ported to Idris, Simon and Izzy said goodnight before heading to bed. Clary and Jace walked in silence to their bedroom. Once they were both inside, Clary shut the door behind them and burst into tears.

Jace was quick to run and comfort his wife. He guided them to the bed where he sat them down and let her cry. He could tell from the moment she walked out of the music room earlier that day that something was bothering her, he saw it even more when she entered the library after putting Celine to bed. Knowing their was nothing he could do to make it better hurt his heart but he whispered something to Clary that they both knew was a promise.

J-"We'll get through this."

Clary looked up at him, her eyes red and filled with fear,

C-"I love you."

J-"Until the day I die."

Before another sob could erupt from Clary, Jace pulled her into a kiss full of love and passion.