I may be,Lawrence is not with his family in 1911, but is in the 1891 and 1901 census.It might be him in PEI in 1911.He is listed as Robert's grandson.
1881 Census Place:River John, Pictou, Nova Scotia, Canada Family 77 Robert LANGILL MM44Ship Carpenter Mary LANGILLFM46 Selina LANGILLF18 Christy Ann LANGILL F15 Melilda J. LANGILLF13 Stephen LANGILLM11 Elleanor LANGILLF4 Geo.Wm. LANGILLM<1Born: Nov (5 months old)
1891 census,River Johnhouse # 195 Robert LANGILLE52married Mary F. LANGILLE51married Christie A LANGILLE25 Stephen P. LANGILLE20 Ellenor J. LANGILLE14 William H. LANGILLE11 HenriettaLANGILLE6 Lawrence LANGILLE4
in Pictou, Pictou Co. N.S. in 1896 (caulker): McAlpine's Nova Scotia Directory for 1896
in Pictou, Pictou Co.in 1901 census, at 144 Prince Albert St. Langille RobertMHeadMMar184160caulker Langille MaryFWifeMOct 4 183763 Langille WilliamMSonSNov 15 187822fisherman Langille Laurence MGrandson S Apr 30 1889 12string job
in Pictou, Pictou Co. in 1911 census, lived at 23 Albert St. Langille RobertMHeadMMay 184169no occ. Langille MaryFWifeMOct183674 Langille StephenMSonWJul187139 mariner, steamboats Langille WilliamMSonSNov188129 labourer, docks Langille Edward HMAd. sonSJan19064