'See' is PIE *sekw- (to follow with the eyes) — the same root gave Latin 'sequi' (to follow).
To perceive with the eyes; to become aware of through sight; to understand or recognize.
From Old English 'sēon' (to see, look, perceive), from Proto-Germanic *sehwaną, from the PIE root *sekʷ- meaning 'to see, to notice, to follow with the eyes.' This root produced Latin 'sequī' (to follow) — originally 'to follow with the eyes' — and is thus the ancestor of English 'sequence,' 'consequence,' 'sue,' and 'pursue.' The semantic link between seeing and
English 'see' and the Latin ancestor of 'sequence,' 'consequence,' and 'pursue' come from the same PIE root *sekʷ-. Latin 'sequī' originally meant 'to follow with the eyes,' so a 'sequel' is literally something you keep watching — the visual metaphor fossilized into a word about narrative continuation.