Ok, I had them get married at the end of Stuart Little 4: Finding Margalo (spoiler, spoiler, spoiler!) Margalo's stick pin was actually in her mother's nest for a reason. It had been given to her mother, Ava Canary, by her grandmother, Anna Avisflava, when she'd proposed to Rafael Canary, her father. It was supposed to be given to her when she proposed to her true love, but her mother's untimely death caused it to fall into her possession. She gave it to Stuart when she proposed to him and he later gave her a green diamond ring, which also had bits of gold and silver on the metal, as you can see, she's wearing the ring on one of her talons. And Stuart is wearing the stick pin.

This is their home in Hebron, Connecticut.