Every now and then I think about Chompy Picasso and how Raphael signed up to be a pet owner but all the evidence seems to point towards him becoming basically a teen dad.
Because we see with Tokka, the six Cosmic Monsters and by extension Volcanthian Fire Beasts as a whole are not just sentient, but sapient.
They can deem you unworthy, they can give permission, they might not all be able to speak in a way humans can understand but they have a mind to them.
At want point did Raph realize this? Was it when Tokka gave him her blessing or was it before then. Did it hit him right away or was it several nights after the blessing did it fully hit him what has happened? How he's made a life altering choice? How his priorities in life would have to be rearranged as he has a son to raise? After Splinter died did Raph gain a fear of making the parenting mistakes he did without doing any of the right things his father did for him?
There had to been some nights where Raph holds Chompy, unsure of what his son needs but knowing he needs something, that same uncertainty that comes from raising another species. Those nights that tested Raph's patience's, the fear of getting angry at his kid, knowing that was something that would stick with him the way but unable to fully control it.
He had to have a talk with the only other active parent he knows; Kirby O'Neil and his own imperfect glory. Learning not just the mistakes, but how to deal with the fear and anxiety. Maybe help Raph work on his own things as well, he is a psychologist after all
No matter what though, he has his brother's with him.
And that changes everything