Feng shui question: can the photos of children be placed in the same room as those of the deceased old man?

This is not a matter of feng shui, but a matter of personal perception.

Some people feel warm, others feel uncomfortable.

Like lamps, some like to be brighter and some like to be darker, which has nothing to do with geomantic omen.

In other words, if grandparents are in heaven, will they bless your family's peace and happiness?

Of course, sometimes when we pray, we ask our ancestors to bless us.

So rest assured, there is no feng shui problem.