Royal couple Prince Harry and Meghan Markle welcomed their first child together on May 6.

A few days later, the world got its first glimpse at the youngest royal – adorable Archie Harrison Mountbatten-Windsor.

Posing in St George’s Hall at Windsor Castle, the former US actress, 37, and Harry, 34, introduced their sleeping newborn to the world.

But just before the pair posed for the official pictures, Harry turned to his wife and whispered to her – and we all completely missed it.

According to lip reader Tina Lannin, Harry said something absolutely adorable to Meghan.

Tina told the Metro that Harry whispered “here we go” before turning to her and flashing a smile.

The royal then looked down at his son and softly said, “He’s so quiet.”

During the press conference, Meghan told reporters Archie had the “sweetest temperament”.

“He’s really calm. He’s just been a dream, so it’s been a special couple of days,” she added.

However, earlier this week Harry revealed his boy hadn’t been that calm as he’d kept him up all night.

On Tuesday, the proud new father visited patients and their families at Oxford Children’s Hospital and gushed over the newborn.

Christine George, whose 17-year-old son is having chemotherapy, revealed: “He [Harry] said he had all this organised, but had a sleepless night last night – not the ideal preparation for his first day at work.”

Meanwhile, the royal couple shared a sweet new picture of little Archie to mark Mother’s Day in the US last weekend. The image, which showed Archie’s feet being cradled by doting mum Meghan, also paid tribute to Princess Diana.

In the background of the shot you can see forget-me-nots, which are said to be Diana’s favourite flowers.

The accompanying caption read, “Paying tribute to all mothers today – past, present, mothers-to-be, and those lost but forever remembered.

“We honour and celebrate each and every one of you.”