yay connections! i'm game for that one. as for knowing her grandfather, since Terin helped rebuild the alienage I'm sure he helped patch up grandpa's house if it was at all damaged during the Battle of Denerim. he'd probably have mentioned he was going to leave and find the Dalish.
well he was best friends with Æolyn (I'm awesome and become biffles with my own characters) who had a thing with Faer so I'm sure he, in the least, has heard of Valan. perhaps an "oh i've heard of you..." scene or banter will be in their future lol