[quote="Simbasdaughterrocks"]This is funny to me everyone is talking about Kopa but Kopa was on the tv shows and in lion king you can see that she is a girl because the marking on her head... Males have a marking on their forehead when they are shown and the females do not... I looked twice the first time a saw them

[/quote]
What TV show? Kopa, as far as I'm concerned, appeared only in
The Lion King: Six New Adventures. Lastly, the anointing paint on the cub's head is an interesting theory, as both "Fluffy" and Kiara were presented with no anointing until after the presentation in Kiara's sake. However, I consider this a theory because nowhere in the films does it state whether the anointing paint is placed or not on the cub's head would confirm the cub's gender.
As for the topic, the cub's gender
in The Lion King remains genderless and "Fluffy" canonwise, but the official entity is Kiara. You have to deny
Simba's Pride as a whole in order for Kopa to be the cub since the two stories cannot be fused together without there being time inconsistenties (and character inconsistenties as mentioned by KentuckyWildcat).