▁departure ▁from ▁the ▁show . ▁In ▁season ▁ 1 4 ▁Sof ia ▁moves ▁back ▁with ▁Arizona ▁because ▁she ▁miss es ▁her ▁but ▁also ▁frequently ▁miss es ▁Call ie . ▁Arizona ▁starts ▁a ▁research ▁project ▁to ▁figure ▁out ▁why ▁mother ▁mort ality ▁rates ▁are ▁so ▁high ▁in ▁the ▁US ▁versus ▁other ▁countries . ▁At ▁the ▁conclusion ▁of ▁season ▁ 1 4 , ▁Arizona ▁dep arts ▁the ▁show ▁to ▁move ▁to ▁New ▁York ▁and ▁it ▁is ▁imp lied ▁that ▁the ▁two ▁may ▁ultimately ▁recon cile . ▁ ▁Development ▁ ▁Cast ing ▁and ▁creation ▁ ▁It ▁was ▁first ▁reported ▁in ▁December ▁ 2 0 0 8 ▁that ▁Cap sh aw ▁would ▁be ▁joining ▁the ▁cast ▁of ▁Grey ' s ▁An atom y ▁as ▁ped iat ric ▁sur geon ▁Arizona ▁Rob b ins , ▁for ▁a ▁multi - ep is ode ▁arc . ▁Initial ly ▁scheduled ▁to ▁appear ▁in ▁three ▁episodes ▁of ▁the ▁show ' s ▁fifth ▁season , ▁series ▁cre ator ▁Sh onda ▁Rh imes ▁later ▁extended ▁Cap sh aw ' s ▁contract ▁to ▁appear ▁in ▁all ▁of ▁the ▁season ' s ▁remaining ▁episodes , ▁becoming ▁a ▁series ▁regular ▁in ▁the ▁sixth ▁season . ▁Spe aking ▁of ▁the ▁new ▁addition , ▁Rh imes ▁said : ▁ ▁This ▁promotion ▁saw ▁Rob b ins ▁become ▁the ▁only ▁les bian ▁series ▁regular ▁on ▁prim etime ▁TV . ▁Rob b ins ▁is ▁described ▁as ▁" qu ir ky ▁[ and ] ▁per ky " ▁by ▁TV ▁Guide ▁Matt ▁Mit ov ich , ▁and ▁" a ▁clear ▁and ▁rational ▁sur geon