Birth Order
Pop psychology swears birth order shapes who you become, but several large, rigorous studies found much weaker effects than the myth suggests.
Blended Families
Blending a family takes years, not months, and research says that's far longer than most families expect going in.
Sibling Rivalry
Birth-order personality is pop-culture catnip, but the research behind it is mixed and far less conclusive than people assume.
Estrangement and Reconciliation
Family estrangement is usually less a single blowup than years of unresolved tension piling up until contact finally stops.
In-Law Relationships
In-law tension is often less about personalities than about two families' unspoken assumptions of what "normal" involvement looks like.