Jump to ratings and reviews
Rate this book

The Lactin Brotherhood #5

Little Doctor, Big Daddy

Rate this book
Dr. Caleb Billings is an endocrinologist with an unusual way to relieve stress when he’s at home. As a Little who engages in age play from time to time, he needs to fully surrender to that part of himself, letting go of all his stress and responsibilities in order to truly relax.

Mack Porter visits Dr. Billings with a situation he can no longer keep to himself. He’s managed to hide his lactation disorder for his whole life, but now, the condition that was the result of unethical experimentation when he was a child has started to affect his life in significant ways.

He can’t be the dominant lover he wants to be while constantly worrying about what his partners will think.

Dr. Billings is an expert in these matters and the only person who can truly help him.


Little Doctor, Big Daddy is part of The Lactin Brotherhood shared world about men who naturally lactate and the guys who need them. This is the third DD/lb lactation kink solo book by Alex Blaine with other authors also writing and co-writing in this universe. If you're interested in writing a Lactin Brotherhood book of your own, please reach out to any of the authors for information.

132 pages, Kindle Edition

Published June 29, 2024

219 people are currently reading
69 people want to read

About the author

Alex Blaine

27 books21 followers

Ratings & Reviews

What do you think?
Rate this book

Friends & Following

Create a free account to discover what your friends think of this book!

Community Reviews

5 stars
129 (32%)
4 stars
113 (28%)
3 stars
107 (26%)
2 stars
41 (10%)
1 star
9 (2%)
Displaying 1 - 27 of 27 reviews
Profile Image for Brooke.
858 reviews577 followers
January 3, 2026
⭐️ 2.5 stars ⭐️

A daddy-type like Mack needed to understand that what was happening to him was a good thing… At least to a Little like me.


A short kinky read, good if you’re into lactation/chest feeding. It’s not really my thing, so this was just… okay.

“Do I get my warm milk now?” I almost couldn’t breathe, the weight of his words and his trust and his need all creating a need within me that I’d never experienced before. “Yes, Little Doc. You’ve earned it.”


Even without the lactation kink (I’ll be very happy if I never have to read milky delight ever again), the romance was too insta for me. Since I didn’t enjoy both the kink and the love story, this was a bit of a miss.

“Whenever you’re ready, sweetheart. Show me how much you like Daddy milk.”


CW and NSFW info (spoilers):
- Age play
- Lactation kink
- Chest feeding
- Mentions of past child medical experimentations
- Brief cock-warming
- Insta-love
- Top/bottom
Profile Image for Peppa.
1,225 reviews101 followers
February 8, 2025
Tbh I expected more of that one…it wasn’t bad but it wasn’t good either. The whole doctor aspect somehow vanished through the story and the pace was way too fast. The characters also really lacked on depth here, i mean I don’t expect from a novella a detailed character with their past and future but well I do expect a bit more than what I got here. Only thing I liked was Caleb’s little space this was really sweet and well done but yeah that it’s.
Profile Image for Tate Webb.
275 reviews4 followers
September 12, 2024
I am willing to accept certain short cuts for insta-love and erotica. I don’t expect books of this type to have a lot of plot or depth of character. This is the third I have read (I read 1 &4 at this point) in the series and the least developed.

For an insta-love it relies heavily on a conversation the MC has with a different character, that we don’t even see.

For an erotica there isn’t enough spice.

This series is a lot of fun. Just, skip this one, and read a different book in the series.
Profile Image for J.P. Sayle.
Author 120 books349 followers
December 27, 2025
cute read

Was a short cute read. I would have like more couple development to show their journey. Insta love isn’t a trope I favor. But if you love that you might love this.
Profile Image for Assh.
934 reviews1 follower
April 30, 2025
3.7⭐
Mack Porter et Dr Caleb Billings
Patien et Medecin
Daddy et boy
Confrérie de lactation

Steve Walters (responsable de la confrérie dans leur ville)

📖
Aider les gens à vivre confortablement est une belle carrière, mais pas le genre de responsabilités que Caleb souhaite à la maison. Il a besoin de quelqu'un qui puisse prendre soin de lui lorsqu'il est le plus vulnérable, et un nouveau patient pourrait bien être la solution idéale…

Le Dr Caleb Billings est endocrinologue et accompagne quotidiennement des personnes souffrant de divers troubles hormonaux. Certains sont graves, d'autres simplement gênants. Mais tous sont importants pour ses patients, et donc importants pour lui. Mais lorsqu'il est à la maison et qu'il n'est responsable de la santé et du bien-être de personne, il a une façon inhabituelle de se détendre. En tant que petit qui s'adonne de temps en temps à des jeux d'âge, il a besoin de s'abandonner pleinement à cette part de lui-même, de lâcher prise sur son stress et ses responsabilités pour se détendre pleinement.

Mack Porter consulte le Dr Billings pour une situation qu'il ne peut plus garder pour lui. Il a réussi à cacher son trouble de lactation toute sa vie, mais aujourd'hui, ce trouble, issu d'expérimentations contraires à l'éthique menées durant son enfance, commence à affecter sa vie de manière significative.
Il ne peut pas être l'amant dominant qu'il souhaite être tout en s'inquiétant constamment de ce que ses partenaires penseront de ses fuites.
Le Dr Billings est expert en la matière et la seule personne capable de l'aider véritablement.
📚


🖋🖋
Profile Image for Mandy (MP Book Reviews).
4,962 reviews46 followers
June 30, 2024
Dr. Caleb Billings is an endocrinologist who helps people with various hormonal conditions on a daily basis. Some are serious and some are merely inconvenient. When he is at home he is a Little to relieve his stress. Mack Porter visits Dr. Billings with a situation he can no longer keep to himself. He’s managed to hide his lactation disorder for his whole life, but hecan’t be the dominant lover he wants to be while constantly worrying about what his partners will think of his leakage.Dr. Billings is an expert in these matters and the only person who can truly help him.

This was a nice story with a little doctor and a dom who needed to accept his lactation and find an acceptable way to drain it. Easy to read and understand. This was a MM story with mature content and a BDSM-like DDLB dynamic.
Profile Image for Kristy Lynn.
399 reviews10 followers
July 22, 2025
Little Doc and Daddy

This series is so fun. Lactating men and the boys/littles who love them and their milk supply. I liked the premise of this story. Mack is older and his milk comes in giving him lots of frustration. He wants to make it permanently disappear. Dr Caleb hopes he doesn’t follow through with the surgery and sends him off with some words to think about and a Brotherhood who can help.

I recommend this story and really the whole series.
Profile Image for Rachel Emily.
4,478 reviews382 followers
July 13, 2024
Just me reading this whole series in like a week LOL

This was cute and fit in well with the overall series. I don't know, something didn't jive for me as well as books 2-4 did? I'd definitely read more from this series though.

For people who want something after Henry the hu-cow books, this series might be right up your alley!
Profile Image for Sue Milkovich.
1,740 reviews17 followers
January 12, 2026
ACHINGLY SWEET

THE LACTIN BROTHERHOOD Book 5. Something about the true love and care that these Books bring forth just makes my heart sing. The loving and the care is what we need more of. When I finish reading I always have a full heart. I HIGHLY RECOMMEND THIS BOOK AND THE LACTIN BROTHERHOOD SERIES!!!!!
Profile Image for Liz Prosser.
310 reviews1 follower
July 24, 2024
sooo sweet!

A lactating man on the edge meets the doctor that changes his perspective and life forever! Super sweet I loved doc little and his man and of course the lactating and suckling! This series is amazing and i impatiently await each new book!
Profile Image for Kristina.
369 reviews1 follower
August 19, 2024
So sweet

Mack and Caleb's book is so sweet. This is a wonderful age play Daddy/Little book. I really liked the way their relationship grew and how perfect they were for eachother. You should read this book.
1,033 reviews
November 7, 2024
Recommended by his doctor!

Mark’s decision to follow the advice given by Caleb, his new doctor, leads to a more intimate relationship between them. Enjoy Mark and Caleb’s discoveries, their dates and all their steamy moments!!!
388 reviews
January 20, 2025
This is a sweet, fluffy age play story that made me smile.
It was only the 2nd of the series that I read and I quite enjoyed it.
It was quick, got me out of my head space for a while and held my interest all the way til the end.

Profile Image for Jessie (thatchickwithabook).
988 reviews16 followers
June 17, 2025
Probably my least favourite in the series so far. Still good, but there was unethical doctor/patient, and someone telling one of the MMCs about the other’s kinks non-consensually (even if he was ok about it), and then they say I love you after 1 day. Just didn’t vibe with this one much.
Profile Image for Vanessa.
236 reviews
December 29, 2025
insta daddy, instalove

This was mainly about the romance not so focused on lactation. Not much description of Daddy/little as it’s a short read. But you get a nice balance of sweet and spice.
Profile Image for Kat_MM_Reader.
188 reviews17 followers
July 23, 2024
Still loving the lactating aspect along with the age play, but these books are never long enough. I feel the story progresses way too quickly.
This entire review has been hidden because of spoilers.
Profile Image for ME E.
584 reviews57 followers
July 27, 2024
Fun and sweet

This was a fun and sweet Daddy/little read. I can't wait for the others in this series. It was nice to see a doctor as the little.... And that nickname. so cute.
Profile Image for Denise GremoryKohta.
4,264 reviews8 followers
September 15, 2024
So fun to read!

I am loving this series. I’m enjoying them so much I that I’m just plowing through them all. And there is still more coming.
1,560 reviews5 followers
February 10, 2025
😍😍😍😍

Another great story. Short but sweet. Great series so far. Need more. Can't wait for the next book in this series!!
Profile Image for Elizabeth.
557 reviews7 followers
May 1, 2025
Another cute book in the series. I felt that it was a little fast moving and forgot the littles work as a doctor.
Profile Image for Tiana.
427 reviews2 followers
October 26, 2025
🤍mm
🤍daddy/little
🤍age play
🤍abdl
🤍endocrinologist mc
🤍doctor x paitent
🤍male lactation
🤍lactation kink
Profile Image for SJ.
2,422 reviews15 followers
January 16, 2026
a lovely story

This is a lovely story with A great plot, adorable characters age play steam and romance. This is a great series looking forward to the next one in the series
Profile Image for Thurman.
654 reviews8 followers
January 4, 2026
I reread this book a few days ago. I don't mind the lactation, but there wasn't much of a story to tell. And I'm kinda sick of littles, especially when they have sex while little. It kinda freaks me out.
If you want a story with instant lust/love and lactation, this might be the book for you.
I think Rewarding His Jock is a better book in this category though.
angst .5/5
heat 2.5/
story 2.5
POV dual
break up no
Displaying 1 - 27 of 27 reviews

Can't find what you're looking for?

Get help and learn more about the design.