Came across your message and had to go to my files as I descend from Catherine Glass and John Penman. Your posting didn't have any dates attached and I don't have Helen listed in my family group but then maybe I'm missing her. To run though the family as I have it:
John Penman b. 6 Feb 1787 in Culross, Perth, Scotland married Catharine Glass b. 6 May 1786 in Burntisland,Fife, Scotland on 22 Jan 1810 in Dalgety, Fife, Scotland. Their children (as I have it) were Richard (my line) b. 16 Oct 1810, Robert b. 30 May 1813, Elisabeth b. 8 Sep 1815, Janet b. 9 Jan 1818, John b. 23 Mar 1821, William b. 18 Dec 1823, James b. 25 Dec 1825 and Catherin b. 26 Mar 1828. I believe that they were all born in Dalgety, Fife, Scotland. With the naming pattern, if Helen was born to this family, I believe she would have been born after Catherin. Does this fit?