The former 30 Rock star and the yoga instructor announced their son's arrival via their social media accounts on Wednesday (17Jun15) by sharing a picture of a baby's hand clutching a finger.

Baldwin writes on, "We are happy to announce the birth of Rafael Thomas Baldwin."

The couple married in 2012 and welcomed their daughter Carmen in 2013.

Alec also has a 19-year-old daughter, Ireland, with his ex-wife, actress Kim Basinger.