Nice chapter, but I found a couple spelling errors you may want to edit.

 "Their still so heavy. You haven't had anypony to help you empty them."

"They're".

But he held her tight, despite his repeated apologies, long aster he finished cumming, still making little jerks with his hips.

"after".

i1.kym-cdn.com/entries/icons/original/000/006/411/Bleach.jpg Yup, very needed.

"Yeah? Well one of us is acting very childish," she said. She stood up and turned around, lifting her tail, flagging it at him and showing off her marehood.

replycandy.com/wp-content/uploads/Ron-Burgundy-Well-That-Escalated-Quickly.jpg

What a minx

<3 ur writing.

"I had a vasectomy. I'm sterile. I can't get you pregnant."

[STUDIO AUDIENCE BOOS]

Lol good fic tho

well now this is going to be a super good story.
and the fact that this is the 3rd part and sequel to the first story makes it that much more interesting.
first story. the son is shining
second story. stormageddon changeling spy

Well, let's put the facts together.
1. she is leaving for an 11 month tour.
2. there are past indicators of possible infidelity:
a. pregnancy test after vasectomy
b. afterglow after trips to other places
c. no reports of what she does
3. the gestation period for a horse is 11 months
Mares typically show signs of pregnancy at around 3 months, so she has had a relatively long amount of time to have "Random Horse Books" send her on a year long trip and have a little extra time after the birth to nurse and raise the foal before either serving a divorce to Night Light or putting up the foal for adoption.

Now then, off to chapter 2.

Ummm... in the last story it was his birthday. In April. In this story it's suddenly June.

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She is there for fathers day.

So will there be a story where she finds out Shining armor is her biological father?

She let go of him and it slapped against his belly, spent of it's load.

*its

Her only reply was knelling in front of him

*kneeling

It has been too long since he'd felt the touch of a mare.

*had

You're testicles ache?

*Your

Daddy knows whats good for his little filly

*what's

8523917 Fixed

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STUDIO AUDIENCE FACEPALMS

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I see you haven't read the second ending to the story before this one.
Here's a link to The son is Shining.

Reading this chapter after finishing second ending to The Son is Shining, is like watching the end of Ground Zeroes cut together with the opening of Metal Gear Solid Survive.

Clarification: I'm not saying that Twilight's Night Light is going to be a dumpster fire, I'm just saying that I like that both chapters meshed together very well.

During the train scene as Velvet and Night Light say their final goodbye, if you pan the camera to the side, you can see the royal caboose, and if you zoom in, then you can see Shining poking his head out the window and see Cadence's hoof pull him back in.