Is zakat obligatory on a commercial shop whose owner died before a year had passed, knowing that the heirs are in need of money and send a portion of it to their grandmother?

Zakat (definition) is not obligatory on the wealth of a deceased person if they die before a full year has passed over it, because it transfers to the heirs. Nor is it obligatory on the heirs unless a full year has passed over their ownership and the share of each of them reaches the nisab (definition), based on the hadith (definition): "No zakat is due on wealth until a full year has passed over it." Zakat is obligatory on growing trade assets, but not on machinery. A child with Down syndrome inherits, and zakat must be paid from their wealth. It is obligatory for children to financially support their impoverished grandmother if she has no provider. And whoever is obliged to be financially supported is not obliged to pay zakat.