Rubuta ci gaba ga wannan sakin layi - Trelawny ya yi aiki tare da Coldstreams a lokacin Raid a kan St Malo da Raid a kan Cherbourg
a shekara ta 1758. Ya zama kyaftin a ranar 14 ga Maris, 1762. Trelawny ya sake ganin sabis a lokacin yakin basasa na Amurka, inda ya jagoranci rukuni na farko na rundunar. Ya yi yaƙi a yakin White Plains a shekara ta 1776, kuma an ba shi mukamin Kanar a rundunar a ranar 6 ga Satumba, 1777. Ya sake jagorantar rukunin farko a yakin Monmouth, inda aka ji masa rauni. An daukaka shi zuwa na farko na rundunar a ranar 5 ga Mayu 1780, daga baya zuwa babban janar a cikin sojojin, kuma an daukaka shi zuwa laftanan-kolonel na Coldstreams a ranar 23 ga Nuwamba 1785. Ya zama Gwamna na Landguard Fort a 1788 kuma ya yi ritaya daga masu tsaron ranar 25 ga Mayu 1789. A ranar 12 ga Oktoba, 1793, an ba shi mukamin Laftanar Janar.