Royal Trio
Prince William, Kate Middleton and Prince Harry had various secret royal engagements this week. Pictured: Prince William, Middleton and Prince Harry during "The Patron"s Lunch' celebrations for The Queen's 90th birthday at The Mall on June 12, 2016 in London. Getty Images/Jeff Spicer

Prince William, Kate Middleton and Prince Harry had several secret meetings this week.

On Tuesday, the three members of the British royal family reportedly had different royal engagements that the public were not aware of as Kensington Palace did not announce their appointments, Daily Star reported. The Duke of Cambridge carried out investitures at Buckingham Palace where he met Jonathan Rea, a superbike champion. Prince William apparently told the Northern Irish athlete that he loves motorcycles, but he puts this interest "on the back-burner" because of his growing family.

On the same day, the Duchess of Cambridge met with psychiatric experts. Meanwhile, Prince Harry attended a Walking with the Wounded reception in London. The charity helps wounded soldiers find new careers outside of the military.

This is not the first time that the palace has kept Prince William's, Middleton's and Prince Harry's duties secret. Last Thursday, the royal trio hosted a lavish gala dinner in honor of the Royal Foundation at Sunbeam Studio in West London. The palace did not announce the gathering and the details were kept under wraps. But some guests shared a snap of their invitation on Instagram.

"The Royal Foundation of The Duke and Duchess of Cambridge and Prince Harry request the pleasure of your company at The Royal Foundation Dinner," the invitation read.

The guests were also requested to wear lounge suits and cocktail dresses for the event. They were asked to be at the venue by 6:45 p.m., ahead of Prince William, Middleton and Prince Harry's arrival. The invitation also included instructions on how to get to the venue. In addition, guests were prohibited from using their mobile phones during the gathering.

"Please note that photography and mobile telephones are strictly prohibited and we ask all our guests to switch off their telephones upon arrival. There will be a professional photographer in attendance," the additional instructions read.

Although some of the royal trio's duties were unannounced, most of their engagements are documented on social media. On Wednesday, the Duke and Duchess of Cambridge went off-roading when they visited the Land Rover factory in Birmingham, England.

Prince William took the wheel of one of the vehicles to test its capability, suspension, grip and camera technology. Middleton joined Prince William in the car. Kensington Palace shared photos and a clip of the royals' off-roading adventure on Twitter.

Later that day, Prince William and Middleton visited the Aston Villa Football Club. The couple met and chatted with the kids on the soccer field. However, Prince Harry was noticeably missing during the outing, and it remains unknown if he had his own royal engagements at the time.