I'd note that most if not all unis see 8 and 9 grades as equivalent to the old A* and don't differentiate between them. So the GCSEs are no barrier since he has effectively maximum marks there, and her A-level grades should give her whatever options. The probable limiting factor will be whether she is doing psychology or a second science/maths subject alongside biology (as some psychology courses want to have two from psychology/biology/maths/physics/chemistry; sometimes geography and further maths are included too).
I'd note if her main interest is in clinical psychology, the outlook is probably a little different knowing that from the get-go. For example, Cambridge (and Oxford, incidentally) heavily emphasise experimental psychology as a research subject, and have very little clinical aspects to the course and in general. Great if you wanted to become a researcher in psychology, perhaps less well suited to someone who wanted to become a clinical (non-research) psychologist). (several of the London unis are similar incidentally, although in her case that's a non-factor if she isn't looking in London)
I'm not too familiar with which unis have a lot of clinical aspects integrated or available as options at undergrad level but it's worth looking into that specifically if that is the main interest! Of course provided the course is BPS accredited then that ticks the main box, but having earlier exposure to clinical things, any clinical placements, and/or the more work experience options in clinical settings would likely be very helpful longer term in securing a position on a DClinPsych course or as an assistant psychologist prior to this, I would expect?