Madonna’s brother, Christopher Ciccone, wrote about how Sean Penn and Madonna dated. Sean Penn was encouraged by his friend who saw how interested he was in Madonna.
Madonna and Sean Penn had their first date on Feb. 13, 1985. They were 24 and 26 years old respectively at that time. After their first date, they became close and stayed together. Ciccone revealed that he shifted to LA to stay at Penn’s home in Malibu.
Just before Madonna married Penn, he made a simple pact with Ciccone to become blood brothers. He cut their thumbs and pressed them together in a symbolic gesture that meant the cementing of brotherhood for him. That was how Christopher Ciccone and Sean Penn became blood brothers.