The Ball Pit || Ten/Donna

A bit of fluff for Ten/Donna.
After taking many trips, the Doctor offers a break for the both of them to go stay with Wilfred while Sylvia goes on vacation. When Donna goes on a grocery run alone, what will she come back to find the Doctor and her granddad have been up to?
A/N: This was a TateTennant secret santa gift for tumblr user 'thedoctordcnna'. I hope the rest of you enjoy it!