I have found the 3 children, William 14, James, 11 & Minnie, 9 living with there uncle James 46 & his wife, Helen & their children at 38 Glasgow Rd, Barrhead, on the 1911 census. No sign of their parents. The eldest, William R. is a Telegraph Messenger for the GPO.
Uncle James & wife Helen were both born in Ireland.
The 3 siblings were all born in Bridgeton & 2 are with William 30 & Mary 29 on the 1901 Bridgeton census.