Ellinor was the one who brought in the property - Lib Assed 1686 in treene of Grenikle - 12s 10d Ellinr Brew & Wm Cowle - the order indicates she brought in property to marriage

Christopher Brew was there in 1639 but Lib vas has it going to son Robt in 1652 'the father deade the sonne entered'
1669 lib vas Robt Brew to Ellin Brew + Wm cowle 'the sd Robt Brew is dead & his daugher Ellin with her husband Wm Cowle is entered as right [heir] accordinge to ye custome of ye countrey' (all these are on MNB CD ! - there is a 1668 Arch will for a Robt Brew in Santan which is probably him

There are no property owning cowles in Santan before your Wm so probably an out of parish match - most likely would be Braddan (Cowle not common in malew) or possibly Ballaugh
however no m/c I'm aware of