Two Men and Half an Angel

One minute Castiel was one of the most feared angels in all of Heaven, the next he is nothing but a fragile child laying in puddle of trench coat. Dean and Sam are thrown into the most terrifying thing they have faced so far: parenthood. Instead of the newest case they find themselves watching the newest Spongebob Squarepants. Just as they think they figured out why Cas is suddenly a child, a fellow angel arrives in the form of a child as well. Can the four of them change the angels back to their original vessels or are they finding themselves a home they never thought they would have?