One Turbo Tax program, 3 returns, 1 now missing

We have the desktop download of Turbo Tax Deluxe. My husband & I filed our joint return, then 1 daughter (24) used it to file her return.  Then our other daughter (22) was home from college on spring break so we let HER use it to file hers using the TT also.  I was just checking to see the status of hers and  noticed that only 2 returns are now listed in the TT file, mine and the younger daughter's, no sign of my older daughter's, who filed back in February.  I should mention that both girls have the same 1st initial, I'm thinking when youngest saved file it had the same name (1st initial & last name) as 1st daughter's--would that erase the 1st one? I'm not finding it anywhere on PC.  Not a HUGE deal, I did print out the paper copies and her return already went through back in Feb, got refund, etc.  Just curious what happened??