"I never knew how much love and pride I would feel," he added. "Lauren in great shape. Thanks for all your kind messages."
While this marks Simon's first child, this makes baby No. 2 for Lauren, who shares a 7-year-old son with ex-husband Andrew Silverman. Lauren was reportedly still married to Andrew when news broke of the socialite's pregnancy in July.
This news comes a week after the cancelation of The X Factor USA.