Why can't this son be sealed to his parents when there are plenty of sources linking them? His siblings have the same problem.
Looking at the son's (GZGL-6WX) record in Family Tree, his Father's (9KG7-8BR) Temple Ordinances are indicated as in need of completion. Parents must be have all the requisite Ordinances completed and be sealed together, before their children can be sealed to them.
We found the record for Nolan R. Ferguson 1921–1996 • GZGL-6WX and see that all of the ordinances for his father, Rue Ellis Ferguson 1896–1984 • 9KG7-8BR are also showing as "Not Available". It could be that these ordinances were completed but are not showing for some reason.
(Clarification: In instances where the ancestors parent's names are known but there is no further information to complete their temple work, the child can still be sealed to the parents.)
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