EI 991 then EI 638 at Dublin
Rome → Dublin → Brussels
Timetable, Dublin time
02:00EI 991 from Rome at the gate
17:30EI 638 to Brussels leaves the gate
15 h 30 apart on the timetable
EI 638 leaves 15 h 30 after EI 991 arrives on the timetable: more than half a day, so not a connection we count.