Help immigration become easier and help families!

My father has been trying to get his green card for more than 10 years. He first tried getting it through his dad, but after 8 years of waiting, his father died from pancreatic cancer. His sister then tried to become a sponsor for him, but they declined. My father cannot get it through me or my sister as we are not of age, and he is getting divorced to my mother. He cannot support us outside of the country anymore.
The law should be changed, allowing it to be easier for a parent to get their papers through their child. For example, if one parent is a U.S. citizen, the child will become a citizen through that parent - NOT because the child was BORN in the U.S. If the other parent is not a citizen, the child would be able to pass the citizenship onto that parent while the child is young.