Who holds the umbrella when it rains: Dean and Jess don't carry umbrella's. If it's raining they walk in it.
Who is the grumpiest in the morning: Dean. And by morning you mean when they both wake up in the middle of the night.
Who worries more when the other is sick/hurt: Jess because Dean is the only one that gets sick.
Who plays pranks on the other: They both play pranks on each other. It gets out of hand.
Who is always the first to suggest cuddling on the sofa: Jess. Less suggesting more just pulling him into the positions she wants him in.
Who insists on creating nicknames for the other: Dean. That's sort of his thing.
Who drools on the other when they’re asleep: Dean probably.
Who says ‘I love you’ first: Jess