Andrew signed a new treaty of alliance with Leszek of Poland in the summer of 1216. Leszek and Andrew's son, Coloman, invaded Halych and expelled Mstislav Mstislavich and Daniel Romanovich, after which Coloman was restored. That same year, Andrew met Stephen Nemanjić, Grand Prince of Serbia, in Ravno (now Ćuprija, Serbia). He persuaded Stephen Nemanjić to negotiate with Henry, Latin Emperor of Constantinople, who was the uncle of Andrew's second wife, Yolanda de Courtenay. Stephen Nemanjić was crowned king of Serbia in 1217. Andrew planned to invade Serbia, but Stephen Nemanjić's brother, Sava, dissuaded him, according to both versions of the "Life of Sava".