Joy for Queen Elizabeth as Great-Grandchildren Baptized on Special Weekend

Max Mumby/Indigo/Getty

Queen Elizabeth is celebrating with her family on a special weekend.

That's because two of her great-grandchildren are being baptized at Windsor on Sunday.

Princess Eugenie and Jack Brooksbank and Zara and Mike Tindall have organized for the christenings of their sons, August and Lucas, respectively, to take place at a poignant time as Queen Elizabeth is marking her first wedding anniversary since the death of her beloved husband Prince Philip today.

There's added symbolism in that both boys are partly named after Philip — it is a middle name for each of them.

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The couples will be joined by their parents — including Prince Andrew and Sarah Ferguson for Eugenie and Princess Anne for Zara — and cousin Prince William and his wife Kate Middleton, The Sun, which broke the news of the occasion, said on Saturday.

Fox Photos/Getty Prince Philip and Queen Elizabeth

The service is set to take place at All Saints Chapel, in Windsor Great Park and a regular place of worship for the Queen. It's also where Eugenie's sister Princess Beatrice got married last year.

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Fresh holy water brought from the River Jordan by Prince Charles following his tour there last week will likely be used in the ceremony.

Indigo/Getty Queen Elizabeth and Prince Philip

Philip and the Queen married 74 years ago on Nov. 20, 1947, at Westminster Abbey. A royal source says she is privately celebrating their anniversary on Saturday following his death on Apr. 9 at age 99.

Buckingham Palace declined to comment when contacted by PEOPLE.