Natasha looked around the familiar quarters she used to share with Clint - it hadn't changed much. The furniture had just moved around a bit and it looked a bit more lived in, but that was about it.

'I think Aunt Pepper said you could sleep in there' Sasha said, coming out of her bedroom and pointing into the room next hers. 'I'm next door and Dad's room is just across the hall way'

'Ok' Natasha replied 'I was just going to unpack so- hey what are you doing?' she asked as Sasha walked over to the bookcase in the corner and began to climb it.

'I'm going into the vents' Sasha replied continuing to climb until she reached the top of the bookcase.

'The vents?'

'The ventilation shafts' Sasha stated 'Uncle Tony likes to change their layout every couple of months, just to mess with me and Dad, and I need to make sure he hasn't touch Dad's nest'

Natasha just nodded, noticing how the young girl's voice had begun to shake as she spoke of Clint's special place. 'Just make sure you stay inside the tower' she said, as Sasha stretched up to open the vent above her, before hauling herself inside. 'Just make sure you are back here in an hour' Natasha called out.

Natasha walked into the spare room Sasha had pointed to and set her bag on the bed before sitting down next to it. As she sat there, letting out a shaky breath, she could make out the sound of her daughter moving along the vents. Natasha smiled to herself; Sasha wasn't as stealthy as her father just yet.

Bozhe moy – what was she doing sending an eleven year old girl into the vents of Stark tower? Natasha silently berated herself. By the sound of it, Sasha normally explored them with Clint, but Natasha knew that the ventilation system could be a very dangerous place, what would happen if Sasha got stuck or lost? She was meant to be protecting Sasha

'Agent Romanoff, forgive me for observing, but I just thought that you should know that Mister Stark has built the vents in this tower extra wide to accommodate Agent and Miss Barton's habits' came the crisp voice of JARVIS, causing the normally alert Natasha to jump slightly.

'Thanks JARVIS' Natasha replied 'just make sure you never spy on me again, otherwise I might have to introduce a particularly nasty virus into your systems' she threatened

'Yes Agent Romanoff' the AI replied with a sigh

'Has Sasha reached Agent Barton's nest yet?' Natasha asked

'She's just a couple of metres away from it' JARVIS reported.

Knowing that Sasha was ok up in the vents Natasha stood up and started unpacking the few belongings she had brought with her.

'Left four, straight on three, along a bit more, sharp right' Sasha muttered to herself as she made her way along the Stark tower vents, trying to be as stealthy as possible. Finally she reached her destination, her Dad's nest. It was located in a dead end in the tower's ventilation system.

It was just as he has left it from the last time they had stayed at Stark Tower over the spring break. Her Dad had set up an Easter egg hunt over the tower for her, Milly and Ed. In the nest, cushions were thrown around haphazardly, with a couple of old blankets tossed into one of the corners and a pile of her Dad's favourite books and magazines in the other.

Sasha began to tear up, the events of the day finally starting to overwhelm her. She had tried to stay brave and strong as she found out that her father was missing and that her own life was in danger, but now, in the place that reminded her so much of her Dad, her facade started to crack. She buried herself into one of the over sized cushions, wrapping her arms around herself as she breathed in her father's familiar scent, which lingered in the material. She actually did not come up to his nest that often as it was considered his private area, but sometimes, especially when she was upset her Dad would bring her here, place her on his lap and they would bury themselves into the many surrounding cushions as he read to her from one of his books. The most recent being The Hobbit, which was lying, half read, on top of the pile.

She missed her Dad. When he had dropped her off at their neighbour's house, she had hopped out of the car, turned around briefly to wave goodbye, before running to greet Mrs Montague, thinking that her Dad would be back to collect her, mission accomplished, the next day. How wrong she was.

Sasha was jolted out of her thoughts by the sounds of people talking beneath her. Trying to be as quiet as possible, she crawled over to the vent opening, where the noise was coming from and peered through the grate. She was directly above the Avenger's communal area.

'Tony, what are you doing?' Sasha heard her Aunt Pepper ask, in the familiar exasperated tone she only used when dealing with her husband

'What do you think I'm doing?' Tony replied. Sasha could just make out that he was tapping away on his Starkphone.

'Tony I thought you said you weren't going to hack into the S.H.I.E.L.D database anymore' Pepper chastised

'That Pep, was before Clint went missing and a certain Agent Romanoff reappeared. I want to know what Fury is up to. Ah ha, here we go...oh that's interesting...'

'What?' Steve asked. Over the years he had given up telling Tony off for breaking into S.H.I.E.L.D's systems and though he loathed to admit it, he liked finding out S.H.I.E.L.D's secrets just as much as the rest of them

'It seems that the mission our favourite Hawk was sent on was originally intended for Agent Romanoff.'

'So why isn't she on it?' Steve wondered. That was a very good question, Sasha thought as she continued to listen in on the adults' conversation.

'Maybe it's got something to do with the shoulder injury Sharon mentioned?' Bruce suggested

'Or it was because she knew that she would be captured and therefore made Fury give it to Clint' Tony said cynically

'Tony!' Pepper exclaimed

'What? You heard that she hasn't just been working been working for S.H.I.E.L.D all this time, who knows what type of organisations she has been involved with.'

'Natasha would never do that to Clint' Pepper said

'The Natasha we knew wouldn't, but we don't know this one' Tony replied seriously, beginning to tap quickly on the tablet

'Tony what are you doing?' Steve asked and Sasha, up in the vent, twisted around to get a better view of what her uncle was looking at. She was starting to wonder how Agent Romanoff knew her father and why she had never heard of her before.

'Tony, you said you were just going to look at the files detailing Clint's mission' Bruce stated

'Yes, but they're not that helpful' Tony replied. 'Look, the master assassin is now living with us so wouldn't you like to know what she's been up to?

Silence filled the room as Sasha watched; wanting to find out more information about the Agent Director Fury had assigned to protect her.

'No, that can't be right' Tony muttered to himself, tapping the screen furiously

'What?' Bruce asked

'JARVIS are you sure you got into all of S.H.I.E.L.D database?' he asked, ignoring his fellow scientist's question

'Yes Mr Stark' the AI replied

'Using Director Fury's level of clearance?'

'Of course Mr Stark'

'Then why Agent Romanoff's file redacted' Tony mused

'All redacted?' Steve asked

'Most of it' Tony replied flicking through the various documents which contained the black scrubbed out marks. 'It seems like all her medical records and mission history has been redacted. The only things that haven't are her Agent identification number and code name. What has she been up too?'

'JARVIS, where is Agent Romanoff' Bruce asked, somewhat hesitantly, trying not to think what would happen if the deadly Russian assassin had been listening in on their conversation.

'Agent Romanoff is getting settled in her room and has just received a call' the AI dutifully reported

Sasha watched through the vent as her uncle clapped his hands together with glee before ordering the AI to tap into Agent Romanoff's phone call.

'I'm afraid sir, that wouldn't be wise' JARVIS protested

'Why not JARVIS?' Tony asked, annoyed that his AI was disobeying him

'Well Agent Romanoff threatened to infect my servers with a particularly nasty virus if she caught me spying on her' JARVIS replied hesitantly

'Just do it JARVIS!' Tony ordered

'Right away sir'

Sasha sat back on one of the neighbouring cushions as Agent Romanoff's conversation started to filter through the speakers.

'...we received this message about half an hour ago' came the familiar deep voice of Director Fury

'And what would you like me to about it?' Natasha asked

'I need you to come and help interpret it' Fury replied 'I have agents now trying to trace the message back to its origin but I need better analysis of the Russian, there was something off with it'

'Fury you have a numerous number of agents who speak Russian' Natasha replied with an audible huff in her voice. 'Besides, I only just got here'

'Natasha'

'Look I know what this is; you're having second thoughts about asking me to look after Sasha aren't you?' Natasha asked 'You think I'm going to get too attached'

'No I-'

'Don't doubt me Director' Natasha whispered in an almost threatening manner'Let Agent Carter have a listen to the message' she suggested

'Agent Carter does not have the skills' Fury pressed

'Agent Carter is perfectly capable at analysing this message' Natasha insisted 'I should know I trained her'. Sasha observed how her Uncle Steve's face had brightened at the mention of his fiancé, before a puzzled look entered his eyes. Clearly Sharon had never mentioned that she spoke Russian. 'So did you check if it was actually Agents Barton and Morse in the message?' Natasha asked

'Ran it through voice recognition and the voices matched' Fury replied

'And what did they say?' Natasha asked

'Well Barton just said Semper Fi' Fury reported

'Just Semper Fi?' Natasha asked with an anxious hint in her voice. Sasha wondered what was meant by those strange words. She knew her Dad had them tattooed on his arm, but she didn't understand why Agent Romanoff seemed so relieved when the Director ensured her that Agent Barton had definitely said 'Semper Fi'.

'So what did Agent Morse say?' Natasha asked

'Well she was more confusing' Fury stated 'we knew it was her, because of the voice recognition, but we haven't worked out what she is getting at. All she does is list some numbers'

'Which ones?'

'She just says '146 3' Fury replied 'She then repeats them again and then the message ends. I've got some of the best cryptographers working on it, but we still haven't managed to get what she is on about'

'I'll rack my brains' Natasha replied 'Keep me posted if you hear anything else'

'Stay safe Natasha and good luck'

And with that the call ended leaving everyone who had been listening on the conversation on silence.

'Well that was interesting' Tony mused

'I still don't believe Sharon had contact with Agent Romanoff all this time and never said anything' Steve muttered pacing around the room.

'Well at least we know they are still alive and hopefully they will be found soon' Pepper said optimistically as she headed towards the kitchen.

The rest of the team, following Pepper's lead, began to go their separate ways thinking about what they had just overheard and wondering if their teammate was going to be alright.

Sasha, up in vents, looked down at her watch in alarm, she had five minutes before Agent Romanoff headed into the vents to look for her. She knew the Agent was tasked with protecting her, but with all she had overheard, she didn't completely trust her and she didn't want her finding her and her Dad's private space. After straightening out one of the cushions and picking up the copy of the Hobbit, Sasha made her way back through the maze of vents to her quarters.

A huge thank you to everyone who reviewed the last chapter! :)