I had a very very vivid (lucid?) dream - it as just sooooo real

i was down stairs in the sitt/dinin room and my granddad was there (been dead 10 years now) (last time he visited me in my dreams was 5 years ago when i was pregnant and had a few problems)

there was like a tunnel sort or worm hole thing and my granddad was urging me to go through it, i was scared a bit and did not really want go but he held my hand and helped me go through this "tunnel" i remember feeling such emotion while going through and happiness and peace. i got through to the other side and i woke up ... i got up and went strait downstairs to have a look b/cause i was so sure that it was so real!

anyone have any ideas for me about what this means?

thank you