Scots sister

← Old English sweostor (inherited)

← Old English swustor (mention)

← Old English sweoster (mention)

← Middle English sister (inherited)

← Middle English syster (mention)

← Middle English suster (mention)

← Proto-Germanic *swestēr (inherited)

← Proto-Indo-European *swésōr (inherited)

← Old Norse systir (cognate)

→ English sister (cognate)

→ Scots guid-sister (prefix)