Published Thursday, 21 March 2013
The Maggie May hitmaker had a baby with girlfriend Sue Boffey when he was just 17, but the couple gave the child up for adoption as they couldn't afford to raise her.
Sarah Streeter got in touch with the rocker after her adoptive mother died in 2008, and the pair has gradually formed a close bond after an initial rocky start to their reunion.
Now Stewart has a penned a song called Brighton Beach which details his relationship with Boffey and Streeter.
He tells The Independent: "It's about a real girl who broke my heart, my first love affair, her name was Sue Boffey and she was the mother of my first child, who was adopted, because we didn't have a pot to p**s in.
"There was no consideration of marriage and it was a real blot on your character to get a girl pregnant in those days. Sarah doesn't know about the song yet, but she'll love it. We've just begun to call each other father and daughter, which was hard because I didn't change her nappies or take her to school, or help her do her homework."
Stewart's album Time will be released in May.