Natasha + Yelena
Finding Steve was a huge relief, especially when Natasha realized that he didn't know what she'd done on Vormir. That was something he didn't need to know for now since she knew that he would very likely be a huge hypocrite about what she did since she knew damn well he would have made the exact same choice if he'd been the one who ended up there.
Natasha hadn't expected to get an encrypted message from her sister and she had no idea what point in time Yelena was from. When she heard the soft, familiar foot falls approaching, she was ready to turn around before the other woman spoke. Her words and the tone of her voice answered that question for her.
Turning slowly, she held up her hands. "It's really me, Yelena," she said.