So CHD is the most common birth defect in humans, and it also exists in cats, so i think it would be a cool thing to have here.

What is CHD? So there are many types, but im looking a specific one called Tetralgy of Fallot. This is categorized by the following:
A hole between the lower chambers of the heart
An obstruction from the heart to the lungs
The aorta (blood vessel) lies over the hole in the lower chambers
The muscle surrounding the lower right chamber becomes overly thickened

This can be lethal if not treated (lions on lioden don't have access to the treatment for this so it is lethal)

Symptoms:
Chronic coughing
Distended abdomen
Fluid build-up in the stomach
Bluish-tinted skin
Inability to exert themselves during exercise
Losing consciousness
Labored breathing
cyanosis (skin having a bluish tint)
failure to grow and develop normally

I'm thinking that the cubs will die at 1 year of age, and maybe have a lower chance of succeeding at cub training because they are too weak to complete it.

Art changes: maybe a bluish tint on the nose and inside of ears. Possibly have cubs lying down.

Health Messages (if you have suggestions feel free to add them):
Birth - Your lioness notices that Cub's cute little nose is a bit blue. So are the insides of his/her ears. However, Cub is acting normally, so she dismisses it as the lighting.
1 month - while the other cubs his/her age are learning to walk, [Name] just lies next to his/her mom. No matter how many times the poor mom pushes [Name] up to walk around, he/she just can't seem to muster the energy to try.
2 months - At this age, most of the cubs are learning to play with each other, but not [Name]. He/she just sits and watches the others, and when he/she does play, it isn't for very long as he/she gets tired easily. He/she seems to cough a lot too.
3 months - While [Name] plays with his/her siblings, he/she suddenly flops over and passes out. Leaving his/her siblings to stare in confusion, poor cub. (suggested by 💀ℌ𝔞𝔯𝔭����💀 (#176515) )
4 months -
5 months -
6 months - The other cubs were starting to learn how to hunt, but [name]was not able to get enough energy to practice with the others. They just watched and coughed weakly. (Suggested by DexterFam2010 #212394)
7 months -
8 months -
9 months -
10 months - Most adolescents are almost half grown by now, but [Name] isn’t. He/she is often mistaken for a cub half his/her age. (Suggested by DexterFam2010
11 months -
12 months - [Name] passed away last night due to heart complications

want to learn more about CHD and tetralogy of fallot in cats?
https://www.pethealthnetwork.com/cat-health/cat-diseases-conditions-a-z/tetralogy-fallot-cats-a-rare-serious-birth-defect#:~:text=Tetralogy%20of%20Fallot%20in%20Cats%3A%20A%20Rare%20but,...%205%20Questions%20to%20ask%20your%20veterinarian.%20

https://wagwalking.com/cat/condition/congenital-heart-defects


If you say no please tell me why!

edit: i got my mom (a pediatric cardiologist) to draw me some diagrams of the heart. the first one is a normal heart, the second is a heart with tetralogy of fallot. the side that is on your left is the right side of the heart because this is what it would look like if you were to look at someone's heart. Its not gory or anything, just long.