She tried to 'smooth things out' [=end an argument or disagreement] with her daughter-in-law, but the damage was done.
They 'smoothed the way' for a quick end to the dispute. [=they made it easier to achieve a quick end to the dispute]
Her time at college wasn't all 'smooth sailing'. [=she had some problems/difficulties during her time at college]
(..) We're never gonna find her in this huge ship. Like a needle in a haystack. Tessa! Great. Great. Oh, that was smooth. No, that was really smooth, letting everybody know we're here. Now they're gonna be looking for us. Better hurry, Crosshairs, before we go into space! (..)2014 Transformers: Age of Extinction