Healthy babies who receive plenty of maternal reassurance during stressful times actually have larger brains than babies who don't get as much motherly nurturing. A study out of Washington University in St. Louis examined the growth of the part of the brain responsible for memory and stress modulation - the hippocampus - and found it to be physically larger and better developed among children who consistently received loving support from their moms (the study did not examine the effect of paternal care), particularly during high-stress situations. The takeaway: You can't spoil an infant with too much love, especially when he's experiencing something stressful, like a cold, a boo-boo, saying good-bye to you, or taking a bath for the first time. So don't hold back- hug away!