I've previously post an issue #1038, detecting an issue in the availability of Children fron parent inside Factory afterInstantiate method.
But it seem, there is another problem with doctrine cascade, I do a little reproducer: https://github.com/mpiot/zenstruck-foundry-issue-1100.

If we create 3 entities:

• A: Parent, OneToMany on B
• B: First child, ManyToOne on A, OneToMany on C
• C: Second Child, ManyToOne on B

Each entity having a PrePersist EventListener, Doctrine and Factory call them in the same order:

• A: PrePersist
• B: PrePersist
• C: PrePersist

But there is a difference in collection accessibility:

• Doctrine:
  • A PrePersist: Count of Bs: 1
  • B PrePersist: Count of Cs: 1
  • B PrePersist: Has A: yes
  • C PrePersist: Has B: yes
• Factory:
  • A PrePersist: Count of Bs: 0
  • B PrePersist: Count of Cs: 0
  • B PrePersist: Has A: yes
  • C PrePersist: Has B: yes

How to use reproducer:
https://github.com/mpiot/zenstruck-foundry-issue-1100

docker compose up
symfony server:start -d
APP_ENV=test symfony php bin/phpunit