When is the Queens real birthday ?

We celebrate the  Queens Birthday in New Zealand on the 1st of June even though her real birthday is on April the 21st.  We celebrate her birthday by having a public holiday every year.   Queen Elizabeth mother's birthday is on August the 4th.    Here are some facts I have found out about Queen  Elizabeth II  when she was crowned Queen on 6 February 1952, Elizabeth became Head of the Commonwealth. New Zealand is part of the Commonwealth.   Elizabeth  is the oldest living Queen . She was born at 2:40 AM. Elizabeth was a nurse  in the army. Here is some more information about the royals if you click on this link Elizabeth II Wiki

On the Queens real birthday in London they celebrate with a 41 gun royal salute  fired by the kings troops. Royal horse artillery in Hyde park at 12:00 Am at noon. There  is also a 62-gun royal salute fired by the honourable Artillery company at the tower at London at 1:00 pm. Gun salute are customarily fired, both shore and at sea ,as a sign of respect or welcome. No particular ceremony is held on the Queens true birthday although the union flag is on public buildings .