Right, Peggy. It take her a moment to process just what she was being told. At first, a wave of sadness. She does have a crush on Steve ever since that car ride just before he became the man he is now. That indomitable spirit was something Peggy knew all too well. Then a wash of confusion and then comes the realization that above all else, the man she cared for /trusts/ her enough to even tell her this. She smiles. It's not forced. Although the moment may seem a bit awkward as she isn't quite sure what to say, she is genuinely happy.