Given a short bio of a person, find the minimal text span containing the date of birth of the person. The output must be the minimal text span that contains the birth date, month and year as long as they are present. For instance, given a bio like 'I was born on 27th of Decemeber 1990, and graduated high school on 23rd October 2008.' the output should be '27th of December 1990'.

Example Input: Arnold Alois Schwarzenegger was born in Thal, Austria on July 30, 1947, the second son of Gustav Schwarzenegger and his wife, Aurelia (née Jadrny)
Example Output: July 30, 1947

Example Input: Kristen Jaymes Stewart was born on April 9, 1990, in Los Angeles, California, to entertainment industry workers
Example Output: April 9, 1990

Example Input: Howard was born in Duncan, Oklahoma in 1954, the elder son of Jean Speegle Howard (1927–2000), an actress, and Rance Howard (1928–2017), a director, writer, and actor
Example Output:
1954