Madonna with Child in stonework (7)
I believe the answer is:
masonry
'stonework' is the definition.
(I've seen this before)
'madonna with child' is the wordplay.
'madonna' becomes 'mary' ('Mary' can be a synonym of 'madonna').
'with' means one lot of letters goes inside another.
'child' becomes 'son' (son is a kind of child).
'mary' going around 'son' is 'MASONRY'.
'in' is the link.
(Other definitions for masonry that I've seen before include "Skill in construction" , "Stonework" , "Building work in stone" , "brickwork" .)