The Aerosmith rocker, 66, celebrated the tot's arrival after his daughter Liv Tyler gave birth on Wednesday, Feb. 11.
"When I got the call that Liv was going into labor, after crying like a baby myself, I immediately dropped everything and went to to the airport to get on the next available flight," Steven said in a statement from a hospital in New York City where Liv, 37, gave birth.
"When I landed I kept calling my daughter Mia who was already helping Liv," he added of his and Cyrinda Foxe's daughter Mia Tyler, who is Liv's half-sister. "She kept giving me minute by minute updates, 'HURRY THE BABY IS COMING!' I made it RIGHT in time before my second grandson entered this world. It was another (God wink) moment of a lifetime for me."
"Love is love is love reflected ANOTHER @LivTyler MOMENT (GOD WINKED AGAIN)…so proud of my Alpha Pup," he added on Twitter of his eldest daughter.
The Grammy winner first became a grandfather in December 2004, when Liv and her then-husband Royston Langdon welcomed son Milo William Langdon. Milo's little brother is the son of Liv's boyfriend David Gardner.
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