Is the husband obligated to fulfill his mother's wishes while his wife's illness is an urgent priority, and what is the Shar'i ruling on prioritizing the mother even in the case of the wife's severe illness?

The mother has a great right over her son, and honoring her is among the most obligatory duties. Similarly, Allah has commanded good treatment of the wife and living with her in kindness. The husband must give everyone their due and balance between rights. If the mother's demands conflict with the wife's demands, the husband must prioritize what is more important. So, if the wife's demands are necessary or a severe need, and the mother's demands are luxuries or can be postponed, the wife's need should be prioritized. This is not considered disobedience but rather compliance with Allah's حكم (ruling/judgment). The guiding principle in this is to prioritize what is immediate over what can be delayed, what is feared to be missed over what is not, and necessities over needs and embellishments.