Scottish help please

Hi

I am trying to find out who the parents are of my 5x great grandmother. What I have is the following:

Christian Sharp has children with Robert Wemyss/Weems/Wemyes

Robert was born in 1766 and I have his baptism record

their children:

Jane born 1791 in Angus. No other details than parents and date

Betty born 1793 in Angus. Again no other details

Margaret born 1794 in Angus. Again no details

Thomas Marshall born 1799 in Perth, Leith. it says "lawful son" of Robert ... and his spouse Christian Sharp

Euphan born 1801 in Dundee, Angus. only parents names given but also has "Euphan Sharp" in the name column, so im thinking this could be a witness?

David born 1805 in Leith. I think it says witness were Andrew Ratbray and George (cant make out the surname but isn't Sharp or any variants of Wemyss

Peter born 1806 (my link) in Leith. This one says Robert Wems and Christina Sharp Sp A N? Witness Peter Couper a Taylor and John Crawford a Carter

I have a copy of Peter's marriage in Leith which doesn't state any info other than deceased fathers name of bride

I believe Euphan died in 1820 in Fife, however burial doesn't really tell me anything to confirm this

Other than that, I cant find any real links either in marriage or deaths of any of them.

Peter eventually moves down to Gateshead but not until the 1830's

Scottish help please