There have been some odd situations with stimulus payments, but it occurs to me that this could be a scenario where the same dependent child could receive two payments.
Let's say a divorced couple has joint custody of a child, which means that in any given year either one parent or the other reports the child as a dependent on their taxes. So let's assume the current stimulus passes and parents are entitled to an additional $1400 payment for a minor child. Father had legal custody in 2020 and files his 2020 return early enough that the IRS will recognize that the child is his dependent, so he gets the $1400 payment for the child. Mother had legal custody in 2019 and that was the last return she filed, so IRS recognizes that the child was her dependent and therefore she gets the money.
This is not dissimilar to people who received the first stimulus checked based on their 2018 return even though they weren't eligible based on their
2019 return which had not yet been filed. The IRS made a point of saying people in this category would not have to repay the money since the whole point was to stimulate the economy and it was recognized that there would be a few inequities here and there. Would they treat this situation the same way?