Sims No Longer Related Since Growing Together Download

Since the release and download of Sims 4 Growing Together onto my Origin on March 16, a family I created two years ago is no longer related. This family consisted of a grandmother with two adult grandchildren, with one of the grandchildren having two kids. The grandmother is no longer related to those two kids (the great-grandchildren). They're only recognized as "acquaintances," but there's no relation between them.

The grandmother also doesn't appear in the family tree of the two adult grandkids, but in the relationship panel, they still show her to be their grandmother. To correct this issue, I've tried modifying CAS, I've tried the RelationshipBit cheat and I've also repaired my game numerous times. I was told by EA Support that other players are experiencing this same issue, but I have yet to receive help. And unfortunately, the other issue is that this family appears as "unplayed," but I've been playing them for over two years.

Experiencing this problem definitely defeats the purpose of owning Growing Together, so I would appreciate any help provided!