Kate Winslet's daughter, Mia Threapleton, might be following in her famous mom's footsteps, but she's doing it on her own terms!The 20-year-old daughter of Winslet and her first husband, Jim Threapleton, has managed to make a name for herself with acting without anyone associating her with her Oscar-winning mom. «Mia's 20 and acting,» Winslet, 45, revealed of her eldest child on the British talk show,.