I have one very good possibility for the father of Samuel Santiago Van Wagner. I had not previously known that you knew his father's first name and when I saw that it was Charles Van Wagner, born about 1837 in New York, I came up with the following which appears to be very close:
William H. and Susan Van Wagner (her last name unknown) of Pleasant Valley, Dutchess County, NY (near Poughkeepsie) had 5 children as follows:
1. Charles E. Van Wagner, b ca1837. In 1850c age 13 years.
2. William A. Van Wagner, b ca1839. In 1850c age 11.
3. Margaret A. Van Wagner, b ca1841. In 1850c age 9.
4. Theodore Van Wagner, b ca1843. In 1850c age 7.
5. James M. Van Wagner, b ca1847. In 1850c age 3 (he may possibly be same as James Matthew Van Wagner who died 8/31/1910 at age 72 at Poughkeepsie).
Do you think that this might be the correct Charles? I have indexes with about 40 Charles', but he is the only unidentified one that has that birth year.
My email: Cvanwagenen@hvc.rr.com
My website: Cvanwagenen.com