Thanks for the links. It appears that tenor clef was a right guess. From what I have seen of cello music, bass and tenor clef are used most, with some treble clef for really high parts.
Thanks in advance if you can make the cello part. If you want to hear how my niece and I sound together, you can hear a mp3 in the duets section. It's a Nocturne by Burgmuller.
Edit ... Oh, I just realized that you Classitar who posted the same mp3! I actually posted mine as after I heard yours. I had forgotten it was you who put up that mp3.
Edit No. 2 ... My niece advises me that , "The cello is normally in the bass clef and sometimes in alto clef if the notes are high." So, tenor clef was wrong. Oops.