There is really not very much to go on here. Problems caused by brain damage can vary widely depending on the particular location and size of the damaged area. Assuming she does not have another stroke (and I can’t tell whether that is a likely or unlikely assumption), she will probably get better rather than worse over time, but how much better is also impossible to predict from the information you give (and very likely impossible even for her doctors). The fact that she often does seem “compos mentis” probably is a good sign, but a full recovery is unlikely.
The parietal lobe, especially the left one, is particularly concerned with people’s understanding of spatial relations and the layout of things in the space around them, and damage there often has effects on spatial cognition (although it can have other results too).
Some of these effects of parietal damage can be particularly weird. One quite common effect of right parietal damage that I happen to know a bit about is left-hemineglect (aka unilateral neglect), in which patients, who may otherwise seem reasonably normal and lucid, fail to pay any attention to the left side of the space around them. (As you probably know, the left half of teh brain deals with the right side of the body, and vice-versa.) They will do things like failing to eat any of the food on the left side of their plate (while complaining that they are hungry) or putting makeup or shaving only on the right side of their face. In extreme cases, they may seem not to hear anything said to them by people standing to their left, although they hear someone standing to their right perfectly well, and respond normally. If asked to draw a picture of a clock face, they will put all or most of the numbers on the right side, and fill in none, or very few, of those that belong on the left. Here you can see some drawings made by people with hemineglect (originals on the left, and patient’s copies on the right).
People will quite often recover, or partially recover, from hemineglect over time, and there are treatments, such as spending time wearing prism-glasses, that seem to help to speed this process up, but no guarantees, I think
Oddly, damage to the left parietal cortex only very rarely leads people to neglect the right side of space. Damage to the left parietal cortex is much more likely to result in language difficulties, however. (This is all assuming we are talking about a right-handed person. With left handers, things get confusing. In some cases you may get a neat reversal of which side damage affects what, but not always by any means.)
Another even weirder symptom often associated with parietal damage, and often associated with hemineglect, is anosognosia, in which patients steadfastly deny that there is anything wrong with them, when there manifestly is. The parietal brain damage may also cause paralysis, for instance of the left arm. If they also have anosognosia, they may deny that there is anything wrong with their arm, and if asked to move they will either insist that they have moved it (when they manifestly have not) or may make some excuse about why they don’t actually want to do so at the moment.
Another oddity is that both of these problems can often be very temporarily fixed by squirting ice cold water in the patient’s left ear. When this is done they may become aware of things to their left again, and our anosognosic would probably realize that her arm is paralyzed. However, after a short while the anosognosia would return, and she would again deny that there was anything wrong with her arm. Although she would probably remember the ear-squirting incident pretty well, she would not remember that it caused her to be aware of her paralysis.
Note, please, that I am not saying that your gran will suffer from either hemineglect or anosognosia, just that they (especially hemineglect, ranging from mild to severe) are fairly common results of right parietal damage. The specific issues she may suffer (and prospects for recovery) will depend on the specific location and extent of the lesion.
Also, be advised that I am not a (medical) doctor.