Mick Jagger?s 29-year-old girlfriend, Melanie Hamrick, is having a baby. This will be Jagger's eighth child. The couple, who have been dating for two years, are reportedly ?over the moon? about the news. According to a source, He?s been incredibly supportive. She knows what a great relationship Mick has with all of his children and can?t wait for him to be a dad again. Jagger's first child was born in 1970 with Marsha Hunt.