Avengers: Endgame's ending gave Steve Rogers and Peggy Carter the happily ever after ending that fans hoped they would have. And while there have been rumors of potential Avengers reunions on the big screen, there’s no reason to believe that we’ll see either Steve Rogers or Hayley Atwell in the MCU in any significant way going forward. That’s not to say, however, that the ending of Endgame for Cap won’t have an impact on the future of the MCU, because what if Steve and Peggy had kids?
Hayley Atwell recently appeared on the Phase Zero podcast and she was asked about the potential of Steve and Peggy having children, and how that could impact the future MCU. We know that Peggy Carter had kids in the main MCU timeline, and the writers of Avengers: Endgame have indicated those kids might be Steve's, though the movies have never stated that clearly. Atwell says that, at least for the moment, the answer to the question is open to interpretation. But she does hope to see that topic addressed in the future. Atwell said…
