The phrase "rough childhood" means that someone experienced many challenging or difficult situations during their early years, which may have affected their well-being and development. Full definition
She was the ice princess who emerged from a poor upbringing and rough childhood in Portland, OR to rise to the top of the sport of figure skating with a ferocious determination and athleticism that allowed her to become the first American woman to complete the triple axel in major competitions. (margoterobbie.com)