Zara and Mike Tindall's second daughter, Lena Elizabeth is the Queen's seventh great-grandchild.
She was born in June, 2018, just two months after Louis' birth in April 2018.
And then in May 2019, Meghan Markle and Prince Harry's son Archie Harrison brought the total grandchildren count to eight!
The 94-year-old monarch's other grandchildren include Savannah Phillips, Isla Phillips, Prince George, Mia Tindall and Princess Charlotte.
"Instagram vs Reality," they cheekily captioned the two photos of little Louis.
The captioned continued: "Thank you for your lovely messages on Prince Louis’s second birthday 🌈. We are very pleased to share today, on Prince Louis second birthday, new photographs taken by The Duchess this April."
On Thursday, the royal couple posted a series of cheeky photos taken of the prince while he was painting.
Like many other children in the UK, Louis was making rainbow-coloured paintings to show support for frontline and essential workers battling the COVID-19 pandemic.
Louis and his siblings are currently isolating at their country home, Anmer Hall, in Norfolk.
The royal update comes after the Cambridge trio recently showed their appreciation for British healthcare workers by taking part in a nationwide “clapping” initiative.
Kensington Palace shared an Instagram video of the youngsters clapping in appreciation for all the healthcare workers fighting on the front lines of the COVID-19 crisis.
“To all the doctors, nurses, carers, GPs, pharmacists, volunteers and other NHS staff working tirelessly to help those affected by #COVID19: thank you,” the caption stated.