Where does “kolmossisarukset” come from?

kolmossisarukset (Finnish) comes from Finnish sisarus, from Finnish sisar, from Proto-Finnic sesar, from Proto-Balto-Slavic swésō, from Proto-Indo-European swésōr, from Proto-Indo-European su-h₁ésh₂-ōr, from Proto-Indo-European h₁ésh₂r̥ — blood.

kolmossisarukset (Finnish): triplet siblings

Definitions

triplet siblings

Ancestry of “kolmossisarukset”, step by step

kolmossisarukset traces back through two separate lines of ancestry.

via Finnish sisarus

Step	Language	Word	Meaning
1	Finnish	sisarus	sibling
2	Finnish	sisar	sister
3	Proto-Finnic	sesar	sister
4	Proto-Balto-Slavic	swésō	sister
5	Proto-Indo-European	swésōr	sister
6	Proto-Indo-European	su-h₁ésh₂-ōr	—
7	Proto-Indo-European	h₁ésh₂r̥	blood

via Finnish kolmonen

Step	Language	Word	Meaning
1	Finnish	kolmonen	three; third gear; trey
2	Finnish	kolme	three
3	Finnish	kolmi	tri-
4	Proto-Uralic	*kolme	—

Every word from Proto-Indo-European h₁ésh₂r̥ →Every word from Proto-Indo-European su-h₁ésh₂-ōr →Every word from Proto-Indo-European swésōr →