Continuity mistake: Alice Tripp is wearing different shoes when she starts walking home from the movie with George Eastman than she is when they are close to where she lives.
Other mistake: When Clift stops rowing, you can still see apparent boat movement in the backdrop film of the lake, more than you could attribute to forward momentum.
Answer: Angela is standing near George when he telephones his mother. Angela is close enough that she can hear the mother say, "Happy Birthday" to her son.
raywest