There is a picture in my sister’s house of my niece as a newborn, being held by her father. She is just three-days old and her father, my brother-in-law Jonathan, is smiling the smile of a proud, new parent. The fact that that picture exists is a testament to this extraordinary man as a father and a person. Two days earlier, Jonathan witnessed his first wife die in childbirth. My niece was saved by an emergency C-section. Jonathan lovingly and sagely posed for that picture so that his daughter would always know how joyous her birth was to him.

Jonathan was immediately thrown into the role of both father and mother to his little girl. He never considered for one moment not raising his child by himself. And he never allowed himself to be hampered by self-pity. He quickly turned his basement into a suite for a live-in nanny and became an expert on all things baby. Fortunately, he has an innate gift with children. He’s one of these people who knows exactly what to say to a child, how to play with a child, and most importantly how to love that child. I’ve never seen anything quite like the rapport that Jonathan has with children.

By the time I knew Jonathan, my niece was three-years-old. We met him for the first time over dinner at his house. We lived in Maryland then and I was visiting my sister with Anna while Ken was away on business. Anna was ten-months-old. Jonathan was a natural when it came to taking care of a child that age, and particularly in all things having to do with girls. That night he had a booster chair, a special plastic Cinderella plate with matching cutlery and Anna’s favorite meal of chicken nuggets ready for her.

Since then Jonathan has been an important resource for Ken and me in both practical and esoteric matters related to parenting. The man is a font of knowledge. In the early years of our parenthood he knew things like where to get Flapdoodles clothing at the best price. He picked up Anna’s hypoallergenic formula in bulk when he was at Costco. All the while his own little girl thrived, growing into a happy well-adjusted child.

When we moved to the Boston area, Anna was two and shortly thereafter I became pregnant with Adam. If Ken was away on a business trip, Jonathan took Anna for a Sunday afternoon so I could have a break. When I went into labor with Adam prematurely, my sister said that Jonathan was understandably terrified for the baby and me. He could barely function until he knew that both of us were safe and healthy.

When Adam presented with fierce infant colic, Jonathan kept Ken and me sane. He had seen this with other babies. In fact, he had seen more of everything having to do with kids than most fathers. He was usually the only Dad at play dates, birthday parties and pre-school events. He knew the deep secrets of the parenting trade and we depended on his knowledge.

When my sister and Jonathan married, my niece walked her father down the aisle and stood under the huppah with him and her new mother. The wedding was a lovely and important testament to the fact that they had already been a family for a long time.

As my children have grown, Uncle Jonathan has become an indispensable part of their childhood. He and Adam have a sweet, funny relationship. The more they tease each other, the more evident it is how much they love each other. Jonathan has a tender and abiding interest in my children. He has steered us toward great pre-schools, gymnastic programs and summer camps. He helped Adam in his quest to achieve balance on a two-wheeler. He convinced me that Anna would do well in sleep-away camp. He was right. He advised us to look into prep school for Adam. Again he was right.

For several years running Jonathan and my sister took care of Adam for an entire week during the summer so that Ken and I could take a vacation on our own. At Uncle Jonathan’s house Adam got ice cream every night, but he also has to go to bed without complaint and make his bed. Every time we picked Adam up after a week with Uncle Jonathan, he lamented that we would undo all of his good work with his nephew in less than 48 hours. And he was right again.

Jonathan is an avid skier and my niece is championship material. At the age of 35 my sister gave in and learned to ski too. From his own experience, Jonathan knew that skiing built self-esteem around sports. He is single-handedly responsible for teaching my children to ski as well as getting Ken back on the slopes with gentle and practical encouragement after almost two decades. Adam is not a particularly sporty kid, but under Uncle Jonathan’s tutelage this winter he became a natural. He went through four levels of ski school in one week.

No doubt Jonathan is a wonderful guy, a loving uncle and brother and a husband par excellence. But every time I look at the picture of him beaming as he held his infant daughter just a day after he buried his first wife, I understand anew that Jonathan epitomizes everything and more that is special about a day dedicated to honoring fathers.

Happy Father’s Day, Jonathan.