Michelle Obama has revealed a touching message she received from her brother after he finished listening to her best-selling memoir on audiobook for the third time.
As she made her way to the event, she received a text message from her older brother, basketball coach Craig Robinson.
"I'm travelling in Europe right now for my #IAmBecoming tour and my brother just sent me one of the best texts I've ever received," Obama wrote on Instagram.
In the text, Robinson expressed gratitude towards his sister for reminding him in her memoir of the memories surrounding their father's untimely death in 1991 at 55 years old.
"As I sit listening to the words of your book for the third time albeit this time by audiobook, it occurred to me that I haven't thanked you for all your memories," Robinson wrote.
"Since I'm the one who is supposed to remember everything, I realised I have blocked out everything regarding dad's death."
The 56-year-old continued, stating that he cried and laughed at the "sadness of the story" and the "comfort" of his sister's voice.
"All I can think of is how much I love my little sister. Thank you," he added.
In the Instagram caption, the former first lady highlighted the impact their father had on them, saying that he gave her and her brother "absolutely everything".
The 55-year-old explained that sharing personal stories allows loved ones to connect, even when they're "an ocean away".
During her appearance in London, Obama spoke with American comedian Stephen Colbert about life in the White House, negative effects of social media and meeting her husband Barack Obama for the first time in 1989.
Dressed in a custom Stella McCartney beaded jumpsuit, the author delighted the audience of 15,000 with an anecdote about how the former US president turned up late for his first day at work at law firm Sidley and Austin in Chicago.
To read all about the event at London's O2 arena, click here.