The Aerosmith legend couldn't be happier for Chelsea - his 25-year-old daughter who is to tie the knot with actor-and-musician Jon Foster.
Steven gushed: "I fell in love with Jon the minute I met him, and Chelsea loves him over the moon. Jon is a great fellow musician and actor. I couldn't be happier."
Jon - who is the younger brother of 'Lone Survivor' star Ben Foster - was incredibly respectful of the 'I Don't Wanna Miss a Thing' rocker, asking his permission for his daughter's hand in marriage at her birthday party in March.
Steven added: "It was beautifully old-fashioned. And it meant the world to me when he came to me and asked for her hand in marriage."
The 66-year-old star also expressed his joy on Twitter, writing: "MY BABY GIRL @CHELSEATTYLER IS ENGAGED TO @INTHEJON!!! I'M OVER THE MOON...LOVE THEM BOTH SO MUCH (sic)"