Hi Lin
You might try looking for Margaret Hood (nee McQueen)'s birth/baptism, from the info I've already given:
Looks as if David's mother was living close by in 1841-
Londown St, Mauchline
Margaret Hood, 60, b. Ayrshire
and still there in 1851 -
Margaret Hood, 74, hand sewer, b. Girvan
This one on Family Search looks a possible:
https://familysearch.org/pal:/MM9.1.1/XYSR-L5TParents shown as
David McQueen and Agnes McMichaelThere is a possible for Thomas, but we don't know much about him, so this is only a suggestion:
https://familysearch.org/pal:/MM9.1.1/XTV7-498Parents shown as
Thomas Hood and Anne MitchellAlso, many Scots families followed a naming convention for their children, so listing children's names in birth order, often gives a good idea of parents.
Family Search are only showing 3 in Mauchline:
1807 Thomas
1815 John
1823 Maria Woodrow
We know that they had more - e.g. David b.c. 1810/11 (probably second son, named after Margaret's father) but I don't see them on SP at the moment. Maybe Thomas was their first child (after Thomas's father)

brevitas