Why didn't little brother work here?
In Ukrainian 'молодший' is used strictly to mean 'younger' in those type of situations, maybe that is why.
Still, right English form is "little" — better than "younger", however.
No, "younger" and "older" are quite the norm in these situations.
He's saying that in English "little brother" is the most common way to indicate a "younger brother". It doesn't imply he's little in size.
now young brother isn't accepted and "little brother" is suggested. this is weird.
Young - молодий, so that's already wrong...
Does дш sounds just like ч? I cannot tell the difference.