Diana has been best friends with Ian Gallagher for years, which is how she first got close to the chaotic Gallagher family and eventually started dating Lip. At the very beginning of their relationship, Karen Jackson deliberately tried to sabotage them by giving Lip a blowjob while Diana was supposed to be tutoring him. Lip confessed immediately, but the damage and trust issues lingered. After months of slowly rebuilding, things were finally solid between Diana and Lip — until they had a stupid argument, Lip got blackout drunk, and slept with Karen again… this time getting her pregnant.