If a smooth sea never made a skillful sailor, so an overprotective mother doesn’t make a successful guide dog. That’s the conclusion of the first study to analyze how mother-puppy interaction influences guide dog training program success. Researchers followed from birth to adulthood 98 puppies enrolled in a New Jersey breeding and training program for guide dogs for the blind, where only about 70% of the dogs graduate as guides. Dogs whose mothers spent the most time licking and grooming them as puppies were almost three times less likely to succeed in the training program, the scientists report today in the Proceedings of the National Academy of Sciences. When the researchers measured the dogs’ ability to stay focused and follow commands or solve complex problems such as retrieving hidden food and navigating a maze, dogs that had been highly cared for as puppies were more anxious. What’s more, puppies raised by mothers that spent more time nursing while lying on their belly were four times less likely to succeed in the program, whereas those raised by mothers that mostly nursed while sitting were four times more likely to succeed. This is because nursing while sitting requires more effort for puppies to reach and stay attached to the nipples, and dogs that didn’t have to overcome such small challenges as puppies might be easily flummoxed by obstacles as adults, the scientists say.