It's a 12A, not a 12, not even a PG. It's totally inappropriate for a glorified toddler. It's not a case of judging, It's a case of what a 3 year old should be exposed to.
12A means that it’s generally not suitable for under 12’s but anyone under 12 must be accompanied by an adult so there’s no age restriction on who can see the film.
If she’s seen the other ones then she should be fine and not scared I suppose, so it’s up to you.
I wouldn’t take my 3/4 year old to it not least because they wouldn’t sit still through it.
I wouldn’t judge unless they started a disturbance.