Happens with kids... there can be many reasons one it’s too hot.. second baby might be uneasy due to teething or hunger or growth... keep feeding baby... also in summer keep baby hydrated

Hey may be because of the heat. . hope the room is well ventilated <br> Also check if she is sleeping more during the day.;

Growth sprut or may be teething.. this will happen every 2-3 months.. its nothing to worry about