Some parents might remember the time they left their child for just a moment, in the grocery store, to return an item to the frozen foods section, unaware that the little one had the knowledge to escape from the grocery cart. They returned to find the grocery cart empty, their heart pounding with panic, and they ran through the grocery store calling the child's name. They found their child a minute later and they felt embarrassed that they had left the child alone. They wanted to hand in their parent badge, feeling like a flop. Mary and Joseph did the same thing.
Every parent makes small blunders from time to time and even some greater ones.
I wonder how many parents who drive two cars to Mass have left a child in church, thinking the other parent had the child. At home they realize their oversight, and rush back to pick up the little child they left in the nursery. They feel terrible but let today's gospel give them some comfort. They do not have to be perfect to be a parent, even a great parent. God made kids resilient.