(The egg on his hands cracks open and splats energon all over Sentinel's face)
Sentinel: –ing...
THE BABIES‼️
Since Cybertron was in a decaying state at the time of Optimus and Megatron's hatching and their egg couldn't develop properly, the brothers were born as small protoforms that couldn't feed on their own or even see at the begining unlike fully formed hatchlings that are similar to a toddler.
This means that Sentinel, instead of having two toddlers that were easier to take care of, was now stuck with the equivalent of two newborn kittens.
While Megatron is the strongest hatchling, Optimus takes the crown when it comes to being the more vocal.