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]
(..) Why didn't you attempt to return to La Guardia? There was simply not enough altitude The Hudson was the only place long enough and smooth enough and wide enough to attempt a landing. Air traffic testified that you were returning to La Guardia but you did not. As I began the left turn, (..)2016 Sully