Yes, this is possibly the link I have been looking for, i.e. why was Carrie M. (Clara?) Wallin sent to live with the VanOstrand/Van Nostrand family after she was orphaned!
It seems there might have been a relationship & possibly her parents, mother or father, were related somehow & they took her in.My Carrie M. Wallin (Clara in 1870 Mentz, NY census) was in Albion, MI between 1850~1863 with Benj & Susan Van Ostrand or Van Nostrand, depending on the writer.
If other Wallin's were linked to Van Nostrand's this might be why.I supect Carrie M. & Mary Ann Wallin are the children of Joseph & Susannah (Susan Cook)Wallin, who came to the U.S. from England about 1845 +/- to settle with other family members.Other possible siblings include John P. or T. and Susan and Richard Wallin.