"You're late."

Natasha shrugged apologetically, but the smile that crept across Clint's lips gave him away. He broke into a grin and dragged Natasha through the door, where she was promptly bombarded by two tiny figures squealing excitedly.

"Auntie Nat!" cried the children.

Natasha hurriedly thrust her box of cupcakes into Clint's hands, then bent down to hug the two small children. "You've both grown so big!" she exclaimed happily, though she hid a small frown as she felt her T-shirt growing steadily wetter.

Laura hurried out and tugged Lila away from her. "Lila, your hands are covered in chocolate icing! Look, you've made Auntie Nat all brown!" she scolded. "Cooper, take your sister to wash her hands."

As Cooper obediently led Lila away, Laura came up and gave Natasha a hug. Bits of chocolate from Natasha's shirt smeared onto Laura's apron, but Laura didn't notice. She ushered Natasha into the living room. "It's so good to see you! Come in, come in. I'm so sorry about Lila - she's been so excited to see you."

"It's fine." Natasha waved a hand dismissively as she gazed down at her shirt to survey the damage. Several small handprints were evident on the pale blue cotton. She sighed. She'd been so happy to change back into clean, ordinary clothes. This shirt had stayed clean for only a few hours.

A cacophony of noise suddenly erupted from the downstairs bathroom. "Give it back!" Cooper was shouting.

Laura sighed in exasperation and shot Natasha an apologetic look. "I'd better sort that out." She hurried out of the room, squeezing past Clint, who was returning from dropping off Natasha's cupcakes in the kitchen. He stopped dead in his tracks, as he realised his partner was covered in muddy handprints.

"Don't," Natasha warned, and Clint quickly suppressed his laugh. But Natasha smiled, and he couldn't help but let out a slight giggle.

"Come on," Clint said. "I'll get you one of Laura's shirts to change into."

Natasha followed Clint up the stairs and into his and Laura's bedroom. She leant casually against the doorframe as he rummaged around, somehow only able to dig out winter coats and jumpers.

"So how did the mission go? Is that why you're late?" Clint asked, tossing a child's stuffed toy onto his bed as he continued to sift through the closet.

His questions were greeted by silence. Suddenly concerned, Clint turned around.

The light atmosphere of a joyful reunion had completely dissipated. Natasha's expression has suddenly grown solemn, and she was staring at the ground, unable to meet his gaze.

"Nat?" He stood up and went towards her.

Natasha took a deep breath and forced her to look up at him. "He got away," she said finally. "We gave chase, but took civilian casualties and -" Her voice caught for a moment, but she continued. "A daycare centre caught fire. We stayed to rescue as many children as possible. Nick pulled the plug after that."

"Oh, Nat..." Clint drew her into a hug. A twinge of guilt began tugging at his heartstrings. "I'm sorry, I should've been there."

"No." She pulled away hurriedly and grabbed his shoulders, looking him straight in the eye. "You're retired. Your duty is here, with Laura and the children. Besides, I'll be fine, I'm a professional." She smiled reassuringly, and although the smile didn't reach her eyes, Clint could tell that the conversation was over. "Now come on, find me a shirt."

Clint gave her one last concerned look, then went back to sifting through Laura's winter clothes in his hunt for a T-shirt.