Birth certificate for Olive:

two addresses should appear on the certificate (they may be the same).

First there is the date and place of birth.
Secondly there is the name and address of the informant. The relationship to the child is often also recorded.

The initials and occupation for the father are suggestive. However, remember that "electrical engineer" at this date does not imply any professional qualification. It probably corresponds to what today we would call an electrician.

Cowley as father's name on the marriage certificate could easily be a clerk's assumption.