Mystery of the discarded grave portraits (Lao Sua)

While exploring the Old Lorong Halwa back in September 2015, i came across underneath a tree, 3 grave portraits. Looking around the area for recently exhumed graves, i could not find any fresh tombs that were recently exhumed. It was therefore very strange that this portraits lay underneath the tree with the picture and text looking clear, not weathered by the elements. Are they from a tomb or maybe from a tablet or urn ?  I am not sure.

Fast forward to 2018, i posted this picture for people to help me translate and this is what i have crowd sourced from the community. The names of the deceased in the portraits are:
李家松 Lee Kah Song (died in 1949)
李朝業 Lee Teow Giap (died in 1967)
李朝任 Lee Teow Jim (died in 1945)

Lee Teow Giap and Lee Teow Jim are probably brothers, while Lee Kah Song may be their father is the theory that one can probably draw from this. However, the mystery remains. Who were this people and why were the portraits discarded? Where are their remains now? If you have a lead, do email me.

Discarded Grave Portrait of Lee Kah Song, Lee Teow Giap and Lee Teow Jim

Discarded Grave Portrait underneath a tree