What's the name of the Disney princess with red hair?

The princess with red hair is called Ariel.

Princess Ai Lier is a fictional fairy tale character in Walter Disney's 28th animated film The Little Mermaid (1989). She is the fourth member of the Disney Princess lineup and is already a mother. Ariel has long flowing bright red hair and wears a lavender shell bra.

In movies and TV series, Ai Lier is the seventh daughter and the youngest daughter of the underwater mermaid Wang Chuandun and Queen Athina.