Alissa is Ashley's twin sister that appeared from Season 3-5. She is portrayed by Maurie Chandler.
She and Ashley have a Mom and an Aunt Rachel who appear in the episode Aunt Rachel Is Here in which it is revealed that Alissa and Ashley's Aunt Rachel is getting Married and that Alissa and Ashley will be in her wedding.In the episode It's Tradition, Alissa and Ashley reveal that their family celebrates their own holiday Sister Celebration since there's so many sisters in their family. It is unknown if Alissa is allergic to milk like her sister Ashley.
- Twice Is Nice! (first appearance)
- A Teddy Bear Pinic
- Barney's Talent Show
- A Scavenger Hunt
- Subway To The Library
- It's Tradition
- The Foolish Wishes
- Sailing Around The Island
- Colors Fish Has Red, Yellow, Black, White & Blue
- Oh, Brother She's My Sister
- Barney's Halloween Party (cameo)
- The Lonely Little Number
- The Lion And The Mouse
- Sharing, Caring, Take Turns and Toys
- I Can Be A Pilot!
- I Like To Be An Artist
- Kristen Has A Surprise: Tell A Friend?
- I Would Like To Be A Baker
- Aunt Rachel Is Here!
- Stephen Gets Lots
- A Different Kinds of Homes In The World
- Barney's Night Before Christmas (cameo)
- There Twins Ashley has a Twin! (final appearance)
- Ashley appeared in Alissa's appearances.