Hi,
Cannot locate Mothers' names but Alexander's father was William and Thomas' father was John. In my source the spelling of Alexander's surname was NESBIT. This was confirmed by a second source.
Regards
Hi, just noticed this post.
My Gx4 grandfather Smith McDowell also married a Nesbitt. His second wife was Esther Nesbitt and her father was also named William. The married in Ballymena on 8th July 1848. I only have the civil record, no parish records but I have other family - McDowell - records for 3rd Presbyterian Ballymena. Esther was born c. 1810 so although it's possible she was Alexander's (born c. 1838) it's a bit of a stretch.