English Art/Literary Poetry & Literature

The narrator is recalling some things from the past.
Evan is the father, Leo - the son.

"[I remember] Evan looking up from the toilet and missing Leo's first real boy pee....."

ok, the question is: what did Evan actually do?
a) was he leaning over the toilet and had to dodge to avoid being - you know what?
b) was he looking OUT OF the toilet (as a room) and so he missed seeing his son doing - you know what - for the first time?
or maybe there is jet another way to understand this fragment?