Trump says 10-month-old Theodore crawled for the first time in the White House just after his grandfather became president.
President Donald Trump's eldest daughter posted video on social media this week of the boy scampering in the executive mansion. She writes that Theodore's crawling was one of "many incredible milestones this past weekend."
It has been nearly 25 years since a president had young grandchildren visiting the White House.
The last time was when President George HW Bush was in office.