I am trying to trace George and Elizabeth Kehler and wonder if anyone can help me please.

They had 6 children –Catherine (1849), Margaret (1851), Elizabeth (1854), George (1856), Louisa (1859) and Alice (1863)

I can find birth records for George jnr, Louisa and Alice but not the older 3.

I can find the family on the 1861 census in Oswestry and I have George jnrs birth certificate from 1856 and they were in Oswestry then, but cant find any records on them before then.

Some census records say George and Elizabeth came from Germany, others say Oswestry. There are a few different variations of their surname (Keelan, Keeley, Kehler, Kebler, Kehlor and Keeler)

Can anyone help to find this family before 1856 as I am going round in circles with it now. Thanks in advance.