Mason is waiting for Nana's blueberry pie and complains that it's taking forever. So Grandpa challenges him to figure out how long forever really is. Is it as long as Grandpa has had his tractor? No. As long as it took Nana to grow the roses to the top of the chimney? Not even close. After a trip around the farm to figure out the answer, Nana's pie is ready. And Mason's finally got the answer: forever is how long he'll love Nana's pie and how long he'll love Nana and Grandpa, too.