Truly bizarre! I've found Margaret's marriage in the register of First Presbyterian of Kensington (Philadelphia) but can't find her in ANY of the many Luffberry/Luffbarry families of the time! There is a household headed by Andrew Luffbarry and his wife, Sarah (nee Garing) but it does not include a "Margaret" in the Census of 1850; she would have only been about 14 and normally in the household of her parents. I'll try searching more, in case she was in another household but this may be very difficult to solve. There were many Luffberrys in Kensington at the time, with similar forenames as well (Andrew was a popular family name). The Luffberrys were originally from a shipwright 'clan', in Perth Amboy, New Jersey. Some members relocated to Kensington (then known as 'Northern Liberties') shortly before the Revolution. If you'd rather continue this in private, you can use my e-mail address at: firstname.lastname@example.org
They continued as shipwrights, then boat builders into the late 1800's, and were well known in the Kensington community.