What is the legitimate waiting period (iddah) that my mother must observe, especially with the prevalence of illogical practices such as wearing shoes all day, even to sleep, and placing them beside the head?

If the mother is in her waiting period (iddah) due to a husband's death, her iddah is until she gives birth if she is pregnant, or four months and ten days if she is not pregnant. She should not leave her home except out of necessity, nor should she spend the night anywhere but in her dwelling. She must avoid perfume and adornment. However, if she is in her iddah due to divorce, her iddah is until she gives birth if she is pregnant, or three menstrual cycles if she is not pregnant, or three months if she does not menstruate. The woman in iddah is not required to wear shoes all day or place them at her head when sleeping, but she must cover her feet in the presence of a non-mahram man.