LONDON - Queen Elizabeth II emphasized the importance of family in her Christmas message this year and her grandchildren brought some Christmas cheer to her husband, Prince Philip, as he recovered in a hospital after a heart procedure.

The 90-year-old prince was forced to miss the royal family's traditional Christmas festivities - opening presents, going to a morning church service, and viewing the Queen's Christmas broadcast - after doctors put in a coronary stent.

Philip had gone to the hospital on Friday complaining of chest pains, which doctors determined were caused by a blocked coronary artery.

Buckingham Palace said it did not know when Philip would be released. "The Duke is in good spirits and will remain in hospital under observation for a short period,'' the palace said.

Prince William and his brother Prince Harry drove in separate cars to Papworth Hospital from Sandringham, Elizabeth's sprawling estate where the royal family gathered to celebrate Christmas.

Prince Andrew's daughters, Beatrice and Eugenie, also came to the hospital, along with Princess Anne's children, Zara and Peter.

The 45-minute visit from the royal grandchildren came after Elizabeth's annual, prerecorded Christmas message to the nation aired. The royal family reportedly watches the broadcast together every year.

The theme of her broadcast - family - was especially poignant with Philip in the hospital recovering. The message was recorded Dec. 9, before Philip, also known as the Duke of Edinburgh, went into the hospital.

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