Where does “caríssimo” come from?

caríssimo (Portuguese) comes from Portuguese caro, from Old Portuguese caro, from Latin cārus, from Proto-Italic kāros, from Proto-Indo-European kéh₂ros, from Proto-Indo-European keh₂- — to desire, wish.

Ancestry of “caríssimo”, step by step

Step	Language	Word	Meaning
1	Portuguese	caro	greatly valued; dear; loved; lovable; of high...
2	Old Portuguese	caro	—
3	Latin	cārus	dear, beloved
4	Proto-Italic	kāros	dear
5	Proto-Indo-European	kéh₂ros	loved; dear
6	Proto-Indo-European	keh₂-	to desire, wish

Every word from Proto-Indo-European keh₂- →Every word from Proto-Indo-European kéh₂ros →Every word from Proto-Italic kāros →