Martha Jellneck.

72 years old Martha Jellneck lives alone in a small apartment in Hamburg. Since she's hampered in walking, she never leaves her home. Her only contacts to the outside world are the young social worker Thomas and a neighbor boy who walks her dog. When Thomas tells her one day that Franz Laub, another one of his clients, has his birthday, she becomes suspicious: that was also her half-brother's name and day of birth - only that he died in WW2...