Elon Musk allegedly got down on one knee and asked Sergey Brin, the co-founder of Google, for forgiveness for an affair between Musk and Brin's wife. 

Unnamed sources told The Wall Street Journal on Sunday that the incident occurred at a party this year and that Brin 

apologised but wasn't speaking to Musk "frequently" despite doing so.

According to unnamed sources mentioned in the same Journal piece, Musk had an affair with Nicole Shanahan, Brin's wife, at the Art Basel exhibition in Miami in December.

According to a source close to Shanahan, Brin and Shanahan were living apart at the time, but according to other sources,  

they had marital issues related to COVID-19 and taking care of their small daughter.

According to court records quoted by the Journal, Brin filed for divorce in January, alleging "irreconcilable disagreements." 

According to unnamed persons familiar with the situation quoted by The Journal, 

Brin and Musk's formerly cordial relationship deteriorated over the course of the following months,  

with Brin allegedly telling his financial advisors to sell his stakes in Musk's numerous companies.

According to the December chronology, Musk's fiancée Grimes was no longer his girlfriend at the time of the affair.