@lizardillo really like your concepts! Love how you put so much personality and humor into your work.
While I love all the details you sneak in, too, I agree with @Asyas_illos feedback: for this prompt, I think you're getting too complicated.
Hope you don't mind, but I did 2 draw overs of these concept sketches -- to show some suggestions for both compositions, instead of just trying to describe it all. Sometimes words can be hard!
First concept draw over:

For me, this works better cropped in--more focus on the characters. You don't need all that environment and you don't need that many characters. I suggest erasing the parent pushing the cub --it could be misunderstood and it's drawing attention away from what's going on in the water. Also, if this is for children's illustration, it's always better to show the main character having the agency to act instead of being forced to act. So if the parent is no longer behind pushing, then it doesn't make sense for the cub to be looking behind at what's going on off-camera. Showing Scaredy Cub looking at the water more effectively communicates the story. You might want to add his little claws gripping the rock, or wiggle lines to show him shaking. And please excuse my really rough sketch of Scaredy Cub's face -- yours is so much cuter!
Second concept draw over:

Again, cropping the composition will help. Of the two, this would be my preference, as I really like the emotion you're showing and the encouragement of the parent, even though we only see them from behind. You don't need so many characters, though. An odd number of characters is more visually interesting, and I question whether or not the birds are needed to tell the story. For the background, ask yourself what you really need to communicate that this is a jungle pond. You might not want to have any rocks in the illustration -- mostly jungles are vegetation, and it will also make for a nice contrast in your color palette, orange tigers against a background of blues and greens. This composition also begs for really dynamic lighting, which would add so much to the illustration.
Hope this helped and hope you don't mind that I drew over your work. Really looking forward to seeing your entry in Critique Arena!