Is it possible for a dead relative to call your cellphone?

My mother got a strange phone call today from a guy who sounded just like her uncle tony, and he had the same thick accent as he used to before he died. He said he was looking for Nicki. Nicki was Tony's brothers name. My mom said she got chills as soon as the phone rang, before she even picked it up and when she answered it, about all of the color came out of her face and she was just speechless. is it possible that this was her uncle tony? (I'm looking for answers from people who have some experience with this stuff) no rude answers. thanks.