Final answer:
Puppies and kittens first begin suckling at birth, which is an important milestone for their survival.
Step-by-step explanation:
Normal puppies and kittens are expected to begin suckling at birth. This is because they are born without the ability to eat solid food and rely on their mother's milk for nutrition. In addition to suckling, they also need to crawl and right themselves after birth, which is the correct answer. Although puppies and kittens do eventually open their eyelids and regulate their body temperature, these milestones occur at different stages of development.
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