Monarch celebrating birthday in private.
Queen Elizabeth II is quietly marking her 96th birthday today.
Officials say the monarch is retreating to the Sandringham estate in eastern England for the big day.
The estate has been known to give the Queen and her late husband, Prince Philip, a refuge from royal duties.
This year, the monarch will also celebrate her platinum jubilee year, marking 70 years on the throne.
Public birthday and jubilee celebrations will take place June 2nd - 5th.