Peter's baby (1961)

Peter Bergmann has celebrated his bachelor party with his good friend William Thorsen. Peter is to marry William's former girlfriend Kirsten on the same day. When they return to Peter's home in the morning, they find a letter from the French hospital "The Little Blue Nuns," asking Peter to come in with his baptismal certificate and have a blood test done. Peter tells William that he had a love affair in Paris while on a business trip for his father's company, but Tony rejected him when he proposed marriage.