I suspect the answer to your title question is directly related to how you feel about Trump fucking up this Republic and its foundation principles. The reason you guys feel the way you do about the moron, Trump, is that he is owning the liberals. The fact that he is destroying our 250 year old Republic barely shows up as a problem for you people. 
The reason those people have more kids may be because they are owning you...and your kind. 
The fact that having more kids so thoroughly upsets you and those like you...may well be the key.
Obviously I cannot say that for certain, but it is something you assholes ought to consider.