Looks like your man was a peddlar!

And they've got Anderson down as male!
A wee bit of local knowledge here I would suggest trying both Stirling and Perthshire when looking for your family births. Drummond is a local name to South Perthshire and there were a great many traveller stopped at Thornhill/Norrieston in Kincardine Perthshire, there was also lots of labour work both there and in Gargunnock in Stirlingshire.
Piece: SCT1841/388 Place: Port of Monteith -Perth Enumeration District: 1
Civil Parish: Port Of Monteith Ecclesiastical Parish, Village or Island: Gartmore Folio: 7 Page: 6 Address: 37 Village Of Gartmore
TODD Matthew M 40
Stone Ware Merchant England TODD Helen F 40 Outside Census County
TODD Janet F 15 Outside Census County
TODD Helen F 11 Perth
TODD Robert M 6 Outside Census County
TODD John M 4 Outside Census County
TODD Anderson M 1 Outside Census County
It looks like wife and all children were born in Scotland but not in Perthshire except Helen (that may not be correct as earlier explanation)
This may interest you
http://www.gartmoreheritage.org/History/history_18.htm