Hi there, I need help in identifying this Japanese song

Hi there,

I'm new to this forum and I come across it while googling for help to identify japanese song.

Here is the song I'm looking for... The title may or may not be Oyasuminasai and it's a song from the 90s. The file was sung by my sister as she memorizes the lyrics .



Really appreciate it if anyone from this forum can help us.

Thank you so much!