It seems as if Donna left her coat when she stormed out however, it will be revealed in a later episode her leaving the coat is what got her and Fred back together.
Nobody seemed to notice that Donna left the house without her coat.
When Lamont is talking to Melvin on the phone looking for Fred, he mentioned to Melvin that his dinner is late. Melvin offered to bring pigs feet to which Lamont replied that he doesn't like pigs feet. However in the final scene Melvin has brought pigs feet and Lamont reaches in to get some.