Gill - I can tell you from the Carpathia Signing On sheets that:
Smith, Hettie Aged 34 years was born in Liverpool Signed on on 7th February 1912 in Liverpool. The ship that she had been on previous to the Carpathia was the Cunard liner the Saxonia. Her occupation was as you say a Stewardess.
Thats all I have - I hope it helps?