It's been a thunder spell from the druid both times.
I gave her owl stats but flavored her as a very small dragon who has a fondness for polyhedral gems. Yep, she's a dice dragon.
I guess that makes my familiar my self-insert character.
Fly-By helps against opportunity attacks, but not against readied attacks.
Which, to me, is fair, because readying attacks requires the foe to sacrifice their main action and reaction.