Yes, Susan's husband, John Francis Webster, was a doctor, and in fact was the first one in Monroe County, NY, where they went in 1803. That whole part of New York was Ontario County, with Genesee being formed in 1802, Niagara in 1808, and Monroe in 1821. One of their sons became a doctor, as well.
I just did some searching on FamilySearch, and found two entries for Barber Allen that said he was born in 1786 in Torrington, Litchfield, CT, married Mary Perry, and died in 1842 in Pavilion, Genesee Co., NY. It was among the Ancestry Files, and listed a flock of children, ten in all, born in Pavilion from about 1815 to 1831. Monroe was just east of Genesee, so the two families may have lived fairly close together, perhaps about 20 miles apart, with Ethan and Charlotte in the same general area.
As for John Allen, he was born about 1784, but I found nothing more about him.However, I've fleshed out the rest of the family a bit, which is always nice.