The birthday alto is a fanmade birthday sing a ma jig. She is yellow, has the same ears, hands, and feet, like all birthday sing a ma jigs, has circle eyes just the same as the birthday soprano, its voice is the same as the prototype Red one, has a purple nose and a red mouth. She has the same shirt like all birthday sing a ma jigs, but the shirt is red with purple polkadots and the words "Happy birthday" in pink lettering. She signs on by saying "Happy Birthday!", enters song mode by saying "This Song is For You!" and signs off the same way as the pink birthday soprano. She sings "Happy Birthday to You" just like all Birthday Sing-a-ma-jigs.
Click here to hear what its voice in singing sounds like.