(CNN) Though the UK celebrates Mother's Day in March, Meghan, the Duchess of Sussex, is still an American at heart.

An Instagram account she shares with husband Prince Harry released a sweet new photo of the newborn royal as the US, along with Canada, Australia and several other countries, celebrated Mother's Day on Sunday.

The duchess, 37, gave birth a week ago to her first child, Archie Harrison Mountbattan-Windsor

"Paying tribute to all mothers today - past, present, mothers-to-be, and those lost but forever remembered," the caption reads. "We honor and celebrate each and every one of you."

In the photo, baby Archie appears to be wrapped in a white blanket and held by his mom. The post also included a quote from Nayyirah Waheed's poem "lands."

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