Dawn French keeps a fairly private life, but on Thursday she delighted her fans when she shared an incredibly rare picture of her daughter Billie from her childhood, to mark her 30th birthday.MORE: Dawn French's house with husband Mark could be a palaceDawn and ex-husband Lenny Henry adopted Billie when she was just two weeks old.WATCH: Dawn French reveals how her husband proposedIn the sweet picture, which was taken when Billie was just a baby, Dawn and her daughter had their heads close