Why Princess Kate Is Skipping the Annual St. Patrick's Day Parade in London

When they receive their traditional St. Patrick’s Day sprig of shamrock tomorrow, the Irish Guards will be smiling — but not at Princess Kate.

Despite carrying out the duty four previous times, Kate will be skipping this year’s ceremony, with her husband Prince William, who’s the Colonel of the regiment, carrying it out instead.

“The Duchess has very much enjoyed the occasions when she has been able to attend, but the Duke is the Colonel of the Regiment and is looking forward to presenting the Irish Guards with their Shamrock,” a Kensington Palace spokeswoman tells PEOPLE.

“The Duchess looks forward to marking St. Patrick’s Day with the Irish Guards many times in the future."

Last year, William joined a then 8-months-pregnant Kate at the annual parade in Aldershot.

This year Kate will be looking after her children Prince George and Princess Charlotte. The following day she is opening a shop that will raise money for a charity she supports,

East Anglia’s Children’s Hospices, in Holt, Norfolk, not far from the family’s country home, Anmer Hall, 110 miles north of London.

The royal mom is focusing on her children in the run-up to her tour of India and Bhutan in April, when she and William will be away for a little more than a week.

Kate’s decision to skip the St. Patrick’s Day event has raised some eyebrows, as the handing out of the shamrock has mostly been done by female members of the royal family for more than 100 years. But palace insiders point out that William is the Colonel — and that is where the formal relationship lies. When he was made Colonel of the regiment in 2011, he was the first member of the royal family to hold the honorary position.