I found two things that might interest you. The first is a 1930 Census where your uncle and great-grandmother are living in the same household. I also found your grandmother and great-grandmother on the passanger list of a ship that came here in 1929. Their place of origin is listed as New Foundland. I'd be happy to send you the image if you email me. Unfortunately, New Foundland is covered in my copy of the 1911 Canadian Census. According the the directory there are still Philpotts in New Foundland.

Ship Manifest
U.S.S. New Foundland
Sailed from St. John's New Foundland (Canada) on Aug. 11, 1929
Destination: Boston, USA.
Arrival Date: Aug 15, 1929

Johanna Philpott Age 24yrs 1month
Female
Single
Occu: Domestic
Speaks English
Can read & write
Country of Origin: New Foundland
Race: English
Birth Place: Kings Cove, New Foundland
Immigration Info: (Not Immigrating) Returning after temporary visit
Last Permanent Residence: Bristol, USA

Margaret Philpott
Female
Widow
Occu: none
Speaks English
Can read & write
Country of Origin: New Foundland
Race: English
Birth Place: Kings Cove, New Foundland
Visa # 153
Issued of: New Foundland
Date: 10/8/1929 (Note: The Canadians record dates like the Europeans day/month/year)
Last Residence: Kings Cove, New Foundland

1930 Census Bristol. Hartford Co., CT
Michael B. Philpott Head M W 30 married at age 30 b. Canada English Heritage Father Canada English Heritage Mother Canada English Heritage Immigrated in 1924 Alien resident Occu: Automotive man Ball B????ing ?????
Celia A. Philpott Wife F W 31 married at age 31 b. Canada English Heritage Father Canada English Heritage Mother Canada English Heritage Immigrated in 1920 Alien resident
Margaret Philpott Mother F W 64 widow married at age 30 b. Canada English Heritage Father Canada English Heritage Mother Canada English Heritage Immigrated in 1929 Alien resident