Now this is a strange name. Very little digging shows it to be a form of Wauchope, an old Scottish name, which appeared first in Ireland in 1733. This variant of the name became well-known in India, an this Matilda is likely the sister of General Charles Wahab.

There is an excellent writeup about the Wauchope family at http://home.att.net/~walkup/wauchope_ulster_book.pdf. I keep a copy on my computer, just in case that link ever dies.

[BBC]29. Long time between the last two children. A bit surprising, but not impossible. No issue given in BBC.