Hi Ann,
I'm afraid I haven't made any further progress beyond John Burnside and Sarah Allen's fathers being William and Alexander, respectively. When they married in 1859, Sarah's residence was Killyberry and an Alexander Allen appears in the 1858? Griffiths' Valuation as being in Killyberry, who I have assumed is Sarah's father.
It's possible that Jane Allen and her father Samuel are relations, but I'm sorry that I haven't made a connection to Drumlamph yet.
Best wishes
Rockford