Jamie Lynn Spears' memoir,, a source tells ET that this has «been a trying» and «painful» time for the 30-year-old actress as she discusses past experiences.While promoting her new book, Jamie Lynn has had a back-and-forth with her older sister, Britney Spears, on social media about the stories told about their relationship over the years. The source tells ET that it was never Jamie Lynn's intention to hurt her sister.«Jamie Lynn has genuinely always wanted the best for Britney and she loves Britney with all of her heart, despite their complicated relationship,» the source says. That being said, the siblings aren't exactly close.