This is old, sorry I've been dealing with my dad and away, but yes, we saw with Brodie multiple fear stages. The first was expected as a pup and then another around 18 months and then around 3 we have a biggy and he hasn't really gotten over his reactiveness from that last change. Deacon, we did not see any similar fear stages, so it may just e a personality type thing, I would NEVER have expected Brodie to be a reactive dog - we spent SO much time exposing him to everything. But the second stage came within COVID and it was hard to overcome it, when the last one came about, we just accepted we have a reactive dog now. It's weird cuz Before that end fear stage, we felt we could deal with anything - that one took us by surprise - and you gotta know, he was in with old folks and young kids and traveled everywhere and he was in classes weekly and competitions and then boom. Best of luck in dealing....