The former Real Housewives of Beverly Hills star first shared a pic of Kristoff on her Instagram after word got out about his passing.
“l’ll miss you ‘Steel’” she captioned the photo.
“An infinite number of hearts are broken because of the passing of Kristoff St. John,” Eileen to PEOPLE in a separate statement. “Kristoff was a loving kind generous sweet hilarious gifted human. He left an indelible mark on all who were blessed to know him.”
“I am so grateful to have been able to work with him and laugh with him,” she continued. “My deepest condolences go out to his family and especially his children, who I know he loves so much.”
Kristoff died at the age of 52 on Sunday, February 3. The LAPD confirmed his passing one day later.
Kristoff’s body was discovered at his home in San Fernando Valley, after a friend stopped by to check on him. His cause of death is currently deferred.