Easy. Hikóómayíi is Arapahoan.

Its broader family is all over the place but contains branches that are Algonquian (containing Hikóómayíi), Iranian, Caddoan, Muskogean, Apachean, and American NWC, at least phonologically. (I also have IE [grammatically but not phonologically] and Austronesian families). Numbers from 1-10 in a few of them to illustrate:

Hikóómayíi: wan hóobo háaθ híišfí ʔáaf póópóof čfí kóočfí čiθ hipá
Sida (Algonquian): kɨn awə hoch iyəhpə kohpə hpapahpə yəhpə tashɨhpə shəshɨch ɨhpɨ

Šāyšbiŋ (Iranian-ish): uŋ āfa θud iyapə ki fāfapə īpə tāyšipə šikiš iɓa
Máséx (Caddoan): sihun asun sút sahkun hunís wárpe yérpe sáhèsírpe skìr tùs
Boowęęts (Apachean): zęę aa tłood eey yęęp haap iishpa teesh siłtsiz bi
Tibayitey (Muskogean-ish): kin obo ład eyo wigye fap yep tiip exšig ibya
Ɨxfaxʸtʸɨq̓ (NWC): χʷɨn awɨ nʷot eɨp̓ʸa k̓ʷɨfʸa ffɨfʸa ɨp̓ʸa θacfʸa cxʸɨs ɨpʷa

Hiurorōt (IE, phonologically more inspired by Blackfoot though it doesn't show up here): ’a’ad pam hen lan ’un ’ihen dō listsich ’uchre kashiē

Untitled (Austronesian): niay hiw ŋə ədiaŋ siaɾ