Sorry but as I said in a later post once a Mormon always a Mormon as far as the church is concerned, same goes for Catholic so unless they kicked him out he still belongs to both as far as the churches are concerned. The Mormons are lax about removing the dead from membership roles.
Apparently Rubio frequents a Christian church in FL.
Just because his parents went to a Mormon church while they lived in Las Vegas, doesn’t mean they converted to Mormonism. I am Catholic and If I go to a Lutheran church, that does not make me a Lutheran. And since Rubio is Catholic he most likely attend Mass in a Catholic Church in Miami