Wow - I can't believe how amazing y'all are! I see that all kinds of new sources have been added and lots of new profiles for her parents and siblings have also been added with more sources. Fabulous, everyone!
Now, though, I am forming the opinion that Lulu wasn't Louisa because (1) Louisa married in England only 2 or 3 years before Lulu married William Bowen in the US and (2) there is a death record for that Louisa in England in the 1930's. Her sister Elizabeth, on the other hand, died in the United States the right time for Lulu to have died here, before William Bowen's 2nd marriage. So ... I now think the Elizabeth in the US, who is probably the Lizzy born in England, is the Lulu I'm looking for. Maybe, as Jo suggested, Lulu was the nickname used to distinguish her from her mother Elizabeth, even though her birth/baptism shows her as Lizzy and "Lulu" seems a more appropriate nickname for her sister Louisa.
Should we go for changing her name to Lizzy with preferred name Elizabeth and nickname Lulu? We can then create another profile for her sister Louisa.
EDITED TO ADD: I just hit more pay dirt. In addition to Violet, there is another child named Lillian, born 17 Apr 1898 and died 23 Aug 1898. Her mother's death 5 May 1898 might have been childbirth related. This nails it - I'm going to change Lulu's profile to Lizzy/Elizabeth's and then add a new one for Louisa.