<prompt> Qedela umusho olandelayo: Njengoba esevele edlale i-England U16 ngo-2011, Wenza i-debut yakhe neRiphabhliki yase-Ireland U19 ngoSepthemba 2014, ngokunqoba ngo-10 ngokumelene neNetherlands U19. NgoSepthemba 4, 2015, wenza i-debut yakhe neRiphabhlikhi yase-Ireland U21 ngokunqoba ngo-4-1 ngokumelene neQatar U23 emdlalweni wobungani eGigg Lane. Ngomhlaka 25 Mashi 2017, uCullen wahola iRiphabhlikhi yase-Ireland U21s ukunqoba i-1-0 ukunqoba iKosovo U21 emdlalweni we-  <response>: I-UEFA Under-21 ine-Championship Qualifier. 