2021 Tax Year - does a dependent minor receiving SSA-1099 as their only income need to file a tax return

If a dependent minor (i.e., a child) receives SSA disability income through a disabled parent, resulting in their own SSA-1099, does the child need to file a tax return? I understand the parents don't include the child's SSA income on theirs - the question is whether or not to file a tax return for the child. I'm a bit of confused from previous discussions:

 

These claim that if the child's only income is SSA benefits, they do not need to file a tax return:

Do I have to claim a SSA-1099 form on my child. If so how??? I don't see where they asked that quest... 

Where do i enter my child's ssa1099 on my tax return 

 

However, it gets a bit confusing in this discussion:

Does my minor child have to file a form for ssa-1099 income. 

 

The initial response from @jerry2000 states that if SSA is the only income a child has, then the child does not have to file or report it. However, in a follow up response, @jerry2000 refers to the Publication 501, and @macuser_22 references the following from this Publication (I updated to reflect 2021 numbers):

 

You must file a return if any of the following apply:

1. Your unearned income was more than $1,100.
2. Your earned income was more than $12,550.
3. Your gross income was more than the larger of—
  a. $1,100, or
  b. Your earned income (up to $12,200) plus $350.

 

Assuming SSA falls in unearned income, this sounds like filing for the child would not only necessary, but common. I'm confused why there is so much ambiguity on the topic.

 

I'd love to hear from tax experts, including the ones who have weighed in on this topic:

@DaveF1006, @VolvoGirl@DoninGA, @jerry2000, @macuser_22 

 

Thank you!