Dolphins, Killer Whales. Alll have complicated and complex social structures and languages that we can't figure out. Plus they have sonar, they can figure out if a person has a tumor or a child
Chimps and Bonobos, both have high intelligence, and social structures, and use tools, unlike dogs, who basically act like 3 yr olds. And dogs stay that way. Lots of couple Lundred get dogs as "practice children", not because they can't have kids, but because they unconsciously are practicing with the dogs or because they don't want to be alone.