Kate Middleton chose a very simple gathering when she celebrated her 34th birthday on Saturday, Jan. 9 in a private get together at Amner Hall. The Duchess of Cambridge enjoyed her day, of course, with her loving husband, Prince William and adorable kids, Prince George and Princess Charlotte, then headed straight to Sandringham on Sunday to attend a mass.

"It will be a low-key celebration," a source told Us Weekly. "Kate doesn't like to make a fuss."

After the simple celebration, the mother-of-two attended a morning service at St. Mary Magdalene Church with her mother Carole Middleton, her sister Pippa Middleton, her brother James and her father Michael.

In another article of Us, it cited that Kate was wearing a black turtleneck with tweed blazer paired with a skirt, all from Michael Kors. She also matched it with a black hat, dark boots and a clutch.

Furthermore, E! Online added that Kate's family entered the church with her 33-year-old husband, the Duke of Cambridge. They were also joined by two of the godparents of their 8-month-old baby, Sophie Carter and James Meade.

They all graced the event to mark the 100th anniversary of the Gallipoli campaign during World War I. The Royal couple chose to leave their two children at home to save them from tiredness.

Meanwhile, it is quite obvious indeed that 2016 is the year of transformation for Kate and William's own family. It has been known that their only son already started going to Westacre Montessori School, which is near their Norfolk home.

In fact, Kate was evidently proud of Prince George as she took photos of him wearing his school uniform and gave a glimpse to everyone as it surfaced on social media. Additionally, she and her spouse are about to visit India and Bhutan later this spring as announced by Kensington Palace.