A great way to start analyzing an obituary is to put all the dates mentioned in it into chronological order.
List all people who were alive when the obituary was written or who apparently survived the deceased. List all people who predeceased the individual who died. Also indicate who was married before the individual died–marriages are sometimes suggested by spouses listed for heirs.
Sketch out other relationships if they are readily inferable from list of survivors.
Use the obituary to see what other records it suggests and remember that just because something is in print does not mean it is corret.