From Wikipedia:
Her investments, particularly in real estate, made her a multi-millionaire. Differing sources state that most of this fortune was bequeathed to either her Gilligan's Island co-star, Dawn Wells, or to care for her dogs. Wells has not commented. The Los Angeles Times reported that Schafer bequeathed 2 million dollars to the Motion Picture and Television Hospital; the money was used to renovate the Hospital's outpatient wing, which was renamed the "Natalie Schafer Wing".
To me when Wells doesn't comment, then it is more probably true.
If it wasn't, then surely a person would comment "I didn't get the money"
It is also easier to look good in old age if you have lots of money.