Is it a nightmare?

Yesterday i told mum bout my dream that i met grandma in my dream. Grandma passed away for 40years and i never met her in my life ,just see-ing her thru the picture that hanging on the wall of my house.Mum felt weird that why i will dreamt bout grandma seems no one dream bout her after my mum dreamt her 25 years ago.Grandma told me angryly to believe and trust in my sister .Few days ago i was quarrel with my sis and having cold war after that. Mum said why so grandma will mention bout sis and know my sis name.Its kind of weird cause grandma never saw my sis and never know her name. Um, shud be granpa telling her that we guess.=)And yet Grandma told me that Chinese New Year is coming soon,she will meet us up downstairs.I was curious that why we meet up downstairs and not our home.In the dream i know that my grandma has passed away.I told her dont go down so early seems daddy is coming back . She asked me back that when daddy is coming back.Then my dream stopped. I was wondering why granma giving me those dream. The main point she's telling me just to believe and trust in my sister? Hmph, i guess so. And the day of my dream is chinese calender 15! Mum said the dream mayb is true that grandma wanna told me something. So, she ask me to buy those 'silver paper' ask burn it to granma. I heard you grandma~ And i will remember what u told me. Rest in peace..=)