Queen Elizabeth II recently canceled her trip to Northern Island, and it alarmed royal family fans as they feared Her Majesty was going through something medically. More recently, it was revealed that she was hospitalized.

According to Reuters, the 95-year-old monarch spent the night in hospital. Buckingham Palace says it's for "preliminary investigations."

"Following medical advice to rest for a few days, the queen attended hospital on Wednesday afternoon for some preliminary investigations." the palace says.

Her Majesty seems to be getting back to her regular duties as she has already returned to Windsor Castle and "remains in good spirits."

The recent news comes after the Queen canceled an official trip to Northern Island and the palace said she was advised to rest by her medical staff.

Aside from the palace's explanation on why she's hospitalized, a royal source spoke to the outlet, saying she was under medical observation because of "practical reasons" and her medical team had already taken a cautious approach.

The Queen is back to her royal duties as she returned to her desk on Thursday afternoon to take some "light duties."

Queen Elizabeth II Cancelled Northern Island Trip

Her Majesty was due to attend a two-day trip to Northern Ireland for the ecumenical service in Armagh but had to cancel the last minute as she was advised to rest.

The service is meant to celebrate the centenary of the partition of Ireland and Northern Ireland.

Since The Queen couldn't attend, Prime Minister Boris Johnson was in attendance on Thursday. Politicians from both sides of the Irish border and Irish President Michael D. Higgins joined him.

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Queen Elizabeth's Health History

The Queen first concerned fans when she used a walking stick at Westminster Abbey earlier this month.

A post shared by instagram

For the past 69 years of her reign as a monarch, the Queen has prevented severe health issues.

However, in 2013, she was hospitalized due to alarming symptoms of gastroenteritis, which causes diarrhea and vomiting.

Then in 2016, she was forced to delay her Holiday travel as she and her husband Prince Philip suffered from "heavy colds." This was not alarming as the outlet noted it could be a natural winter cold or flu.

At the time, they spent their Christmas festivities at Sandringham instead of their usual residence of King Lynn.

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