They're not the same. Everett Ross and Thadius Ross have separate identities and storylines in the comics. Their powers, if any, and character arcs are completely different.
Since I don't have a lot of information about this specific story, it's hard to say exactly who Mike Ross is. He could be an ordinary person with an interesting personal story that involves some sort of growth or change symbolized by 'big boy pants'.
I'm not sure specifically who 'ann b ross' is just from this phrase. It could be an author. Maybe it's someone who has created works within the realm of 'fantastic fiction' which might include elements like magic, otherworldly beings, or extraordinary adventures.
Their friends like Marshall and Lily could be important characters. Marshall might offer legal advice about the adoption process as he's a lawyer. Lily could be the one who gives them tips on taking care of a baby since she has experience with her own child.
The Barney true story is that Barney was a popular children's TV show character. It was a purple dinosaur who taught kids about friendship, sharing, and various positive values through fun songs and simple stories.