The happy family beamed as they posed for pictures together with Minnie Mouse in front of the Cinderella castle on Thursday, wearing matching white T-shirts with mouse ears on the pockets.
Once inside the Magic Kingdom, six-year-old Maddie was transformed into a princess for the day with a trip to the Bibbidi Bobbidi Boutique.
Jamie Lynn, 23, shared a picture of her little girl all dressed up on her Instagram page, which she captioned, "Princess Maddie!! #disney2014 #thewatsons."
Thursday also marked Jamie Lynn and James' five month wedding anniversary. The couple tied the knot in New Orleans on 14 March, in front of some 150 guests including the bride’s big sister Britney Spears.
Maddie served as a flower girl at the wedding, and sparkled in a little white dress, while Britney’s two boys Jayden James and Sean walked as ring bearers.
The couple had been engaged for a year before tying the knot; Jamie Lynn excitedly shared news of their engagement by showing off her beautiful diamond ring on Twitter.