Mike,
Could you e-mail me at
srm_4@hotmail.comI think I've got the information you're looking for. Mary Casselman was born in 1811 and died in 1906. Her husband William Henderson was born in Ireland. Your ancestor Sarah was born around 1845. I've only got 15 kids listed for Mary & William. Matilda Township is located in Dundas County. Casselman is a big name in that area.
There's a pretty good possibility that you and I are distant cousins.
Shaun