I had a dream last night about my grandmother who died recently?

my grandmother died in march, and just last night i had a very short dream. i was in a kitchen somewhere and i was watching my grandmother hoover the kitchen. she suddenly stopped and was staring into space and i asked her "whats wrong nan?" and she replied "there's someone standing over there, there's a ghost over there" and she was pointing into space. it scared me when i woke up. plus she was always a very spiritual person believing in ghosts (when my great grandmother died she could smell her perfume sometimes when watching tv, and said she could see certain things) what could this dream mean?