My youngest brother was born when the rest of us were in high school and late elementary school. My mom went into menopause soon after having him. To be honest, I as a young teen was very embarassed when she was visibly pregnant because that meant all my friends knew that my 40-ish parent were - gasp - still having sex
He was the best thing to happen to our family. I know it was hard for our mom. She was working full time and the pregnancy was tougher than her other ones, and she went back to work after having him. But, he brought all of us so close together and gave our family many joyful, unique experiences. Like a bunch of teenagers, adults and their fiances waking up at 5 AM to open presents from Santa, because our 5 year old brother just knew he would bring gifts to all his brothers and sisters.
Our parents were never without sitters because we all clamoured to watch him and our teen friends loved having him around too. Because he was often around older siblings, he could communicate with anyone and at a young age moved between mixed aged groups with grace and ease. He kept our parents young too. When he was little, all of their peers started to look old, like almost grandparents. Our parents grew visibly more energetic, fit and youthful in their outlook than their friends because of keeping up with an energetic boy. Their friends were all sitting on their rumps growing old but our parents couldn't let themselves do that.
Our mom passed away several year ago, and we all are there to mother and guide him. We adore our little brother, and have been closer to him over the years than anyone who hasn't had an unexpeted much younger sibling can imagine.