Continuity mistake: In Beth's death scene check the arrangement of pillows under her head. It changes several times before and after she dies. (01:32:45)
Continuity mistake: Nala's eyes change from blue to green quite often during the movie.
Suggested correction: Her eyes were green the whole time. It's just lighting making it look like they changed color.
The correction assumes these lions are filmed, but they are drawn. So if the eyes are blue, they coloured it blue and if it's green they coloured it green, on purpose.
They are colored to emulate different lighting conditions. Note that the fur is also different colors in the different shots.
A darker shade of the same color isn't the same as a whole other color.
Continuity mistake: Susan's bang is significantly above her eyebrows when she watches the parade at Bryan's house. That same evening during Thanksgiving dinner, it touches her eyebrows.
Continuity mistake: When the two kidnappers realise the baby is drooling on them from the skylight, Mantegna in the shot from above is holding the pen in his right hand. It was in his left a moment earlier. (00:25:10)