In general, Duchess' voice is so beautiful, and mothering that it can cheer anyone up. Helps that her voice actress would later voice Miss Bianca in The Rescuers and its sequel.
The ending where Thomas O'Malley becomes a father with Duchess and the kittens.
Thomas O'Malley,The Alleycats, and Roquefort rescuing the cats. Special mention goes to the scene where Thomas and the Alleycats start attacking Edgar while Roquefort is trying to rescue the cats from a locked chest.
Marie's interaction with Duchess throughout the film. Sure, she may be a bit spoiled and a "tattletale" according to Berlioz, but she has a very close relationship with her mother, especially in the "Scales And Arpeggios" scene.
Marie and Roquefort Jr's interaction throughout the book "Disney Marie" by Kitty Richards, released in 2007. It's very sweet to watch, especially during the moment where Marie witnesses Roquefort Jr about to get eaten by a stray cat and Marie scares the kitten away so he won't get eaten. Then there's the illustrations like Marie cradling Roquefort Jr and Roquefort Jr sleeping on Marie.
Outside the film, Marie meeting guests at the Disney Theme Parks takes Marie's sweetness Up to Eleven. Especially if you see any child, whether it's a boy or girl, hugging her and depending on what you say to her. It will make her feel touched and happy.
The 2007 Book called "Disney Marie A is for Adorable A Fabulous Alphabet!" is cute to read. But if you own a CD player or a computer be sure to read along with the CD playing because the music heard throughout it is sweet and relaxing to lesson to. Especially the theme song for the book that is heard in the intro and outro to the book complete with lyrics below.
Bonjour everyone have you meet Marie? She's the prettiest kitty that you ever see. Folks far and wide always smile with delight. When they see her soft fur that's so fluffy and white. Marie loves to sing and Marie loves to dance. Her home is in Paris a city in France. She loves to dress up and go shopping each day. Then eat a sweet treat in a sidewalk cafe. If you can ask do you know her the people say "Oui". In French that means yes and it's easy to see why everyone loves Marie. Everyone loves Marie.
O'Malley's selflessness. He clearly has the hots for Duchess when they first meet. When the kittens come out while they're flirting, he's understandably surprised. But he continues to help them all get back home. Many guys dating single moms usually beat it as soon as they find out about her children because they don't think of kids very highly or aren't ready to take on such a responsibility. But while O'Malley almost walks off, he quickly calls himself out and changes his mind. He wins Duchess' heart and takes on the role of a surrogate father incredibly well to her kittens. He's truly a street cat with a heart of gold.
The fact that Madame Adelaide is completely fine with taking in Thomas and even treating him like she treats her beloved pets. She obviously has no idea what Duchess and the kittens had experienced when they were missing, or who this strange tomcat was, but just the fact that Duchess and her kids have bonded with him is enough to convince Adelaide to accept him into her house. This despite that Thomas is clearly a feral street cat and not a purebreed pet like Duchess.