In GF2, at the wake of Mama Corleone, Connie enters from the left and drops a tissue or handkerchief. It then appears like she was going to pick it up but changes he mind. In movies, small faux pas' like that don't make much difference to the scene. I've seen it happen on B'way where and actor drops something and another actor picks it up. It's more critical in a play because it might become a obstacle or hazzard for the next scene.
That's an interesting remark. There's a scene in "On the waterfront" where Brando picks up the glove which the girl had accidentally dropped. He knew how to use this "accident" creatively. In fact Brando alway embrased situations like these. The cat was also an "accident". Maybe Talia Shire wasn't as flexible as Brando.