The Rohirrim were the Twilight Men, the second "class" men as I understand it. Now Eowyn's grandma was a descendant of Numenor, right? The Morwen of Dol Something?

i can't remember....
Now could it be possible that Eowyn, Eomer & other descendants of Morwen to at least have longer lifespans than most Rohirrim?
Like, the ordinary Rohirrim span is around 80, the Gondorians around 150-200. Could it be possible that Eowyn or Eomer received at least 100 years of age?