All for a girl named Rose

Stark

Natasha pressed the heel of her palm into a gash in Rose's side.

"Tony?!?" Steve asked in disbelief.

"He's the only person besides Banner who could possibly help her. She received a fatal dose of that stuff, there's no antidote. She'll die in less then four hours."

"He could arrest you, turn you in, give your location to Ross. How do you know if he'll even help? You're putting yourself at risk." Steve was concerned for her, but at the moment she didn't care about herself about survival or freedom. She cared about her daughter and if she was going to have to give up her freedom for her daughter's she'd do it in a heartbeat.

"He'll help, he has a soft spot for kids. Before he gets here however, I want you to leave. Head back to the Red Room facility and wait with Yelena until he leaves. He may arrest me, I don't care if much rather take that risk then watch my daughter die. But I don't want to loop you into this. Okay? If I get arrested you're going to have to take care of Rose." Steve was stubborn, she doubted she would follow her instructions. She hoped that he could at least take care of Rose.

She called Tony. She hoped he would pick up. On the last ring he did. 

All Steve could hear was "Hi... No Tony... I need your help, there's a young girl she was poisoned by the Red Room... WOULD I BE CALLING YOU IF I HAD THE ANTIDOTE... about 14... she's in really bad shape... no... yes... please... fatal... bad shape... four hours.. why would I be lying to you.. I know what I'm risking by doing this and I know what you would be too... no... she's just a kid... thank you... you have no idea.

"He'll be here in an hour and a half. He agreed to help, however we have to turn in the Black Widows. The UN has been hunting for them for quite a while. So you're going to have to stay out of the facility. About a mile west from it is an abandoned greenhouse, Yelena will show you where it is." 

Natasha left out the part where she agreed to surrender herself too.

Steve decided to stay be her side until Tony arrived. Natasha looked her daughter over again, brushing her wet hair that had started to freeze away from her face. Natasha found that cuts, scrapes, bruises, and gashes littered her exposed skin. All were fresh. 

They knew. They had too. They knew I was coming for her. Melina. Сука. 

Yelena joined them a little while later. After getting the run down on their situation Natasha pulled her close.

In the rolling syllables of her native language she whispered what she hadn't told Steve. She doubted  Tony would let her go.

Only once did Rose open her eyes. She groaned and looked up at Natasha.  Who in turned looked back down at the girls crystal blue  eyes.   

Natasha greeted her in an attempt to keep her conscious, however she was greeted with unintelligible mumbling before the girl slipped back under.

When it was finally time for them to leave Yelena pulled her sister in for a long hug. Knowing that it might be the last time she sees her.

Steve is confused when Natasha pulled him down for a lingering kiss. He was unaware what she had agreed to.

"I'll see you in a minute." Natasha smiled at them as they turned and left. 

When Tony finally landed in a quin jet. Upgraded to Tony's standards. Natasha's heart was racing. 

"Hey Natalie, long time no see. Oh- wow she is... not looking good. She looks like she was hit by a truck. You both do." Natasha sighed, Tony hasn't changed one bit.