To add to your list of Corrins, Gary Walker of Ontario has discovered German MI 254 in the IoMFHS book of MIs. This includes two more infants, William John Joughin and Jessie. The entry reads:

Ref. 254 German MI's "In affectionate remembrance/of /WILLIAM JOHN JOUGHIN/ the dearly beloved son of /Henry William & Mary Anne CORRIN/ who died November 6th 1877/aged 8 years/Like the stars of the morning/ His bright crown adorning / They shall shine in their beauty/Bright gem for his crown/ also JOSEPHINE ANNIE & JESSIE/ who died in infancy/also of the above/MARY ANN CORRIN nee JOUGHIN/ died at Chicago, USA August 18th 1891/ aged 66 years/ Asleep in Jesus/ also in memory of/ HENRY WILLIAM CORRIN/ the beloved husband of the above/Mary Anne/born at Castletown April 26th 1888/ died November 13th 1901/ Until the day break and the shadows flee away"ALL Surnames underlined

There's just about room for WJJ towards the end of 1869. Jessie would presumably come between Josephine Annie (1) and Lydia.