A/N: I do not own any of the characters. This is just a headcanon story focusing mainly on a possible FitzSimmons future life together. I decided that Fitz and Simmons would have wanted to name their daughter after someone they could both idolise – one of the greatest woman of science in history, Marie Curie: Polish-born French physicist and chemist.
Leo awoke to the sound of loud crying echoing throughout the room. Not wanting to wake Jemma, he gently pushed their duvet covers aside making sure to keep her properly sheltered from the unforgiving harshness of the winter air. He stepped towards the crib that had been placed meticulously at the foot of their bed, where a small bundle was moving restlessly about.
"Hush now, my little monkey," he whispered to the small figure, gently lifting their baby out of her tiny crib and positioning her into his arms. "You're going to wake your mummy."
He began to rock his arms to and fro in an effort to calm his little one. God, she's perfect, he thought to himself as he stared down at his daughter's face. He could see a lot of Jemma's features in her, with just a hint of his curly tuft on her own tiny, fragile head. Leo looked over at the still, sleeping figure of his wife on the bed and a smile began to form on his face.
"I'm going to tell you a story, my little Marie," he crooned softly at the tiny bundle in his arms, "A story of two best friends who fought endless battles against many enemy organisations, super-powered baddies and many more alongside a small team of SHIELD agents who they felt were like family to them…"
Jemma rolled over on her opposite side, her eyes fluttering awake to find Leo sitting at the windowsill of their small bedroom carrying a tiny bundle in his arms. She could hear him muttering softly under his breath, his eyes full of wonder and love as he stared down at their daughter.
"…she had always disapproved of her best friend's love for monkeys, but then came you and we both decided that you would always be our little monkey," Jemma heard Leo whisper, his voice gentle as ever.
His eyes were heavy with fatigue, and he could feel them slowly shut on their own accord. Leo was suddenly jolted awake when he felt a petite hand on his shoulder. He looked up to see Jemma beaming down at him and at Marie, her face as lovely and radiant as ever.
"Let me hold her. You need to sleep," she remarked pointedly at the bags under his eyes, placing a soft kiss on his cheek before wrapping her arms protectively around their daughter.
"Has daddy been bothering about monkeys again, my little one?" she crooned softly, her smile growing wider as she glanced towards Leo. Marie reached for her mother making small, bubbling noises as if she were replying to her mother.
"Hey, she loves my stories, I'll have you know," Leo retorted, flashing a mischievous grin towards his wife and their daughter. Jemma poked out her tongue in return, laughing at the gesture.
"Oh, Fitz," she giggled, before turning back to the windowsill and singing their daughter a lullaby that her mother had always sang for her when she had trouble sleeping at night or when her nightmares haunted her.
Leo watched his two girls for a few moments before approaching them, wrapping his arms around Jemma's waist.
"…he said 'You've been beside me the whole damn time' and, from then on, they vowed to never leave each other's sides ever again. The end," he said, reaching around his wife to kiss their daughter on her forehead before placing a loving kiss on Jemma's cheek as well. "Goodnight."