Transact SQL :: Query Works Even If Column Not Exists In Subquery

When I execute the below queries it works perfectly where as my expectation is, it should break.

Select * from ChildDepartment C where C.ParentId IN (Select Id from TestDepartment where DeptId = 1)
In TestDepartment table, I do not have ID column. However the select in sub query works as ID column exists in ChildDepartment.  If I do change the query to something below then definately it will break -
Select * from ChildDepartment C where C.ParentId IN (Select D.Id from TestDepartment D where D.DeptId = 1)

Shouldn't the default behavior be otherwise? It should throw error if column doesnt exists in sub query table and force me to define the correct source table or alias name.

create table TestDepartment
(
DeptId int identity(1,1) primary key,
name varchar(50)
)
create table ChildDepartment
(
Id int identity(1,1) primary key,

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