Barron Trump clearly takes his role as uncle seriously after he was spotted keeping his big sister Ivanka's baby son Theodore entertained at Donald's inauguration.
While dad Donald Trump signed the formal nominations for his cabinet picks after being sworn in as the 45th President of the United States, the ten-year-old played peek-a-boo with his nine-month-old nephew. Ivanka smiled at her baby son who watched as Barron played with him before becoming distracted.
The youngest son of the President joined his older siblings on Capitol Hill on Friday as their father was sworn into office. Wearing a blue tie and coat, Melania's only child seemed at ease as he stood beside his mother.
Young Barron will be the first son of a President in the White House in 54 years as the last President to have a son living in the White House was John F Kennedy Jr.
However, Melania and Barron will not be moving into the most famous house in the world for at least six months following Donald's inauguration to allow Barron to finish the rest of his school year without disruption.
Although he attended the earlier festivities, Barron was not present later in the evening as his parents danced together for the first time as first couple. The pair were soon accompanied by Mike Pence and his wife Deborah along with Donald's older children and their spouses as they danced to My Way by Frank Sinatra.
Before leading his wife in dance, Donald complimented her, saying: "My number one supporter, Melania. What she puts up with, thank you, honey." The First Lady looked stunning in a gown by Hervé Pierre, while Ivanka wore a Carolina Herrera number and Tiffany Trump chose a lilac strapless gown by Simin Couture.