Answer: Most azaleas like growing in shade, or at least part shade so I'm assuming that's the exposure. Some of these suggested replacements will need part sun of 4 to 6 hours or at least some sun when they bloom (such as what they would receive when planted under deciduous trees).
Calycanthus floridus - Carolina allspice a native that also comes in yellow; Kalmia latifolia - mountain laurel is also a native. Many different colored flowers to choose from. There's even a very short one called 'Elf'.
Manhonia aquifolium aka Oregon grape aka Oregon holly grape, is a native evergreen whose leaves resemble holly with fragrant yellow flowers. It will grow in shade. It tends to sucker so you will need to prune off the shoots, but in full shade it will grow a little more slowly for you. It tends to grow with an open informal look.
There are hardy fall or spring blooming camellias. Most grow very slowly, but some get to be very large over time, so choose a cultivar that will mature to a height you want. There are some that only grow to about 4'. They almost never need pruning. Mine bloom between Thanksgiving and Christmas in zone 7 and total shade, but the buds or flowers can often get blasted by a heavy early fall or late spring freeze. The buds of the semi-double flowers seem to tolerate the frosts better.
Hope one of these suggestions is just right for your mom's landscape.
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