▁station ▁Gar rett ▁Ryan ▁as ▁Young ▁Nathan ▁( in ▁flash back s ) ▁ ▁Series ▁over view ▁ ▁Development ▁and ▁production ▁On ▁January ▁ 1 8 , ▁ 2 0 1 3 , ▁CBS ▁placed ▁a ▁pilot ▁order , ▁under ▁the ▁title ▁Un author ized ▁Greg ▁Gar cia ▁Pil ot . ▁The ▁pilot ▁was ▁written ▁by ▁Greg ▁Gar cia ▁and ▁directed ▁by ▁James ▁Bur rows . ▁ ▁Cast ing ▁announ c ements ▁began ▁in ▁February ▁ 2 0 1 3 , ▁with ▁Will ▁Ar nett ▁first ▁cast ▁in ▁the ▁lead ▁role ▁of ▁Nathan ▁Miller , ▁a ▁recently ▁divor ced ▁man ▁whose ▁life ▁is ▁complicated ▁when ▁his ▁parents ▁decide ▁to ▁move ▁in ▁with ▁him . ▁Ar nett ▁originally ▁book ed ▁the ▁role ▁in ▁second ▁position ▁to ▁Up ▁All ▁Night , ▁whose ▁future ▁was ▁uncertain ▁at ▁the ▁time . ▁Mar go ▁Mart ind ale ▁was ▁the ▁next ▁actor ▁cast , ▁in ▁the ▁series ▁regular ▁role ▁of ▁Carol ▁Miller , ▁Nathan ' s ▁v ibr ant ▁but ▁med d les ome ▁mother . ▁J . ▁B . ▁Sm o ove ▁then ▁joined ▁the ▁series ▁as ▁Ray , ▁Nathan ' s ▁good ▁friend ▁and ▁cam er aman . ▁Short ly ▁after , ▁Mary ▁Elizabeth ▁Ell is ▁signed ▁onto ▁the ▁role ▁of ▁Deb bie , ▁Nathan ' s ▁happ ily ▁married ▁sister . ▁In ▁early ▁March , ▁Beau ▁Br id ges ▁joined ▁the ▁series ▁as ▁Tom ▁Miller , ▁Nathan ' s ▁father , ▁who ▁moves ▁in ▁with ▁Deb bie . ▁Michael ▁Rap ap ort ▁was ▁the ▁last ▁actor