My guess would be that it had something to do with ensuring her and her child(ren)'s right to the property after the husband's demise. Especially if he was married previously and/or had kids from a prior marriage, the inheritance rules would work against her and her child.

Good hypothesis. I just found the deed. Need to poke around on maps. Find disposition. Her spouse was older, widower twice over. Her 2nd. Widow to consumption. First I've seen of this parcel. Trying to pin down her move from NY to MI. She's in NY in 1855 and MI by 1864. Nine years is a long time.