I mean, are we ignoring the Next Avengers iteration of her son with Bucky Cap, which is semi-canon since he and his team have shown up via time travel?
Because, barring the mind wipe she's currently got that prevents her from remembering him, Bucky's got a fairly solid relationship with her, longer than the ones she had with Clint or Matt, and probably more enduring than the one she had with her deceased husband back in the Silver Age.