Sims children who die don't become ghosts

I'm also having the same problem.  I have seasons and my child sim died due to extreme heat, the Grim Reaper reaped her along with her mom but when I click to her mom's urn, I can plan a funeral but not with her urn.  I invited her to my lot, and she just appears as normal, not in her ghost form but when I shift click to edit her, I can't edit in CAS since the game says I can't do it while the sim is dying.