Scientific Parenting Diary

Halloween is here! Your child comes home with a bucket overflowing with candy—chocolates, gummies, lollipops, sour treats, and more. For kids, it's pure excitement. For parents, the questions are just beginning. How much candy is too much? Are some treats worse for teeth than others? Is it better to enjoy candy at once or spread it out over several days? What if your child insists on one more...

Your child brushes twice a day—so why do cavities still happen? If baby teeth eventually fall out, do they really need treatment? And when children proudly announce, “I can brush my own teeth!”, is it finally time for parents to step back? The transition from baby teeth to permanent teeth is more than a dental milestone. It's also a time when children are learning to take responsibility for th...

When children begin losing their baby teeth, parents often find themselves with a whole new set of questions. Why has one child already started losing teeth while another has not? How long should it take for a permanent tooth to appear? Why do the two sides of the mouth seem to change at different speeds? Why do new permanent teeth look so big, crooked, or crowded? And if a permanent tooth starts...

Your child has a room full of toys—so why do they still come over and ask: “What should I do now?” This does not necessarily mean they do not know how to play, lack imagination, or are not independent enough. When no one provides the next step, children have to do something surprisingly complex: come up with possible activities, choose among them, get started, and then stay engaged long enough for...

Your child knows how to get dressed, clean up, and prepare to leave the house—so why do they still need so many reminders? It is easy to assume that once a child can complete a task, they already know how to manage it independently. But if we slow the process down, we may notice something different: the adult is often the one noticing what is unfinished, checking for mistakes, deciding what should...

When children sincerely agree to do something later, why does it sometimes seem to vanish from their minds when the moment actually arrives? And why can a simple reminder suddenly bring it all back? At the heart of this puzzle is  prospective memory —our ability to remember to carry out an intention in the future. For preschool children, remembering what they are supposed to do and spontaneously r...

If a five-year-old can follow directions—put on their shoes, grab a water bottle, brush their teeth, and get ready for bed—does that mean they already know how to plan? Not quite. Following a plan and creating one are two very different things. For young children, planning doesn’t begin with calendars, schedules, or carefully organized to-do lists. It starts much smaller: understanding that events...

Why do preschoolers keep asking for “five more minutes”—even when we have already warned them that it is time to stop? For young children, leaving the playground, putting away the blocks, ending a favorite activity, or settling down for bed is not simply a matter of listening or refusing to listen. A successful transition draws on developing skills such as attentional shifting, inhibitory control,...

Why do preschool children seem to slow down exactly when it is time to leave the house? And why does saying “hurry up” often make the morning feel even harder? In this episode of The Scientific Parenting Diary, we explore how young children develop a sense of time, why clock-based phrases like “five more minutes” can feel abstract to them, and why everyday routines place a surprisingly heavy deman...

Around age five or six, many children move from preschool, daycare, or early childhood programs into a more formal school setting such as Kindergarten. To adults, this may look like simply changing schools. But for children, it can mean a major shift in daily rhythm, teachers, classmates, rules, routines, arrival time, and expectations for independence. In this episode of The Scientific Parenting...

After a long-haul flight, why can a child feel exhausted during the day but suddenly become wide awake at night? Why might they struggle to sleep even when they are clearly overtired? Why do mealtimes feel off, and why might hunger show up in the middle of the night? In this episode of The Scientific Parenting Diary, we explore what happens inside a preschooler’s body after crossing a major time d...

Why can a child clean up toys at preschool, but leave toys everywhere at home? Is it a lack of discipline, or is something deeper happening in the preschool brain? In this episode of The Scientific Parenting Diary , we start with one ordinary family struggle: toy cleanup. From there, we explore how cleanup is connected to executive function, self-regulation, free play, creativity, and a child’s de...

In this final episode of our preschool immunity series, we are not adding more strategies or new information. Instead, we step back to examine a more fundamental question: where are the boundaries of what can actually be influenced in a child’s immune system? After understanding how immunity develops, why symptoms vary across seasons, and why children respond differently in the same environment, m...

Many parents put significant effort into “boosting” their children’s immunity — through vitamin C supplements, fruit, soups, and various health products. But an important question remains: Are these efforts actually helping? In this episode, we step away from simply askingwhat to feed, and instead take a closer look at some of the most common — and often overlooked — misconceptions in everyday nut...

In the same season, the same classroom, and the same environment, why do some children seem relatively stable while others appear more reactive? We often describe this difference as “weaker immunity” or “poor constitution,” but that explanation is often too simplistic—and can easily lead to unnecessary worry. In this episode, we take a step back and look at the question from a deeper biological pe...

As spring arrives, many parents notice something subtle but unsettling—their child’s body seems to “change.” There are more fluctuations, more visible reactions, and sometimes it raises a natural concern: is something wrong with my child’s immunity? In this episode, we take a step back and look at the question from a different perspective. Is spring really a season when children are more vulnerabl...

When parents hear the word “immunity,” they usually do not think of it as an abstract biological concept. Instead, they think of very specific moments in daily life: a child starting preschool and suddenly having more runny noses, coughs, or occasional fevers than before; or those times of year—especially in spring—when a child’s health seems to fluctuate just enough to make parents wonder whether...

In a child’s world, winning and losing are never just about the outcome. What truly matters is the meaning they attach to losing. In this episode, we take a long-term developmental perspective on how parents shape a child’s win–lose mindset during the critical transition years of 4 to 7. We explore how children link outcomes to self-worth, how family climate influences mastery versus performance o...

In this second episode of our series on preschool competitiveness, we shift from understanding to action. Last time, we explored why children around ages 4–6 suddenly care so deeply about winning and why losing can feel overwhelming. This episode brings us back to the game table—the moment when your child loses, says “It’s not fair,” questions the rules, or melts down. What is actually happening i...

For adults, Lunar New Year often represents culture, tradition, and heritage. For preschool children, however, it is experienced very differently. They may not grasp the historical meaning behind the holiday, but they deeply remember the atmosphere—the colors, the food, the sounds, and the emotional tone of the family gathering. In this episode of The Scientific Parenting Diary, we explore from a...

Around ages four to six, many children suddenly seem to care deeply about winning and losing. A game that used to be fun can quickly turn into tears, frustration, or angry protests of “It’s not fair.” When adults see this, it’s easy to worry: Is my child becoming too competitive? Are they a sore loser? Did we do something wrong? In this episode of The Scientific Parenting Diary , we step away from...

For preschool children growing up in English-dominant environments, understanding Mandarin often comes much earlier than speaking it. In the previous episode, we explored why this is a normal and healthy stage of bilingual development—not a failure on the child’s or the parents’ part. In this episode, we take the next step and ask a more practical question: What kinds of Mandarin input are actuall...

Preschoolers growing up in an English-dominant environment often understand Mandarin far better than they speak it. Many parents wonder: If my child understands Chinese, why do they always answer in English? Are they really learning the language, or just passively hearing it? In this episode ofThe Scientific Parenting Diary, we look at how young children process two languages from a developmental...

Many parents have experienced this moment: you’re upset, trying to explain what went wrong, and speaking more firmly than usual—when suddenly your child goes quiet. They stop responding, stop moving, and seem to shut down completely. It’s easy to interpret this as defiance, avoidance, or refusal to listen. But for children between the ages of four and six, something very different is often happeni...

When it comes to education planning in the United States, the 529 plan is often presented as a universal solution. But for families living in California, the real question is rarely whether to use a 529—it’s how to use it without making costly mistakes. With no state tax deduction, a high number of private-school families, and widespread confusion about financial aid, many parents find themselves...