Ok, I remember Oivia singing seeing a call and response song in bird land where she sings birdland and all of the birds repeat, I always found if funny how cats (Chip and Dip) were hanging around a bunch of birds and never seened to have a tast for one.
I remember a sketch where Oscar was at Celina's dance studio and he was arguing with her about her not beeing grouchy enough, and her and the kids proved to oscar that could be as grouchy as he could by singing the song "doing the grouch" to which Oscar admitted thay they were grouchy, but he still had his little nitpicks about it just to give her a hard time to which she responded in a bit of frustration but not to much because she knows how oscar is " Oh Oscar".
I remember Lillian sang a version of the song wake up because nap time was over at her daycare.
There was the time Ruthie was sleeping over at Big Birds with Elmo and she was teaching them the "Hay It's a sleepover song, and there was also the time she sang Be My Echo with an opra singer ( I don't remrmber har name).
I also herd a song on the Mfiles where David and Olivia were singin the song called sing (a different song and man can she ever belt out a tune).