Magnus Maximus
The peace with Magnus Maximus was broken in 387, and Valentinian escaped to the west with Justina, reaching Thessalonica (Thessaloniki) in summer or autumn 387 and appealing to Theodosius for aid; Valentinian II's sister Galla was then married to the eastern emperor at Thessalonica in late autumn. Theodosius may still have been in Thessalonica when he celebrated his "decennalia" on 19 January 388. Theodosius was consul for the second time in 388. Galla and Theodosius's first child, a son named Gratian, was born in 388 or 389. In summer 388, Theodosius recovered Italy from Magnus Maximus for Valentinian, and in June, the meeting of Christians deemed heretics was banned by Valentinian.