When a child's mother (usually the son) refuses to acknowledge the fact that "her baby" is growing up and will always try to be involved in whatever they do. This is most commonly seen in these three scenarios; 1) getting a driver's license 2) the first date 3) going off to college.
Mother: Oh, I just can't believe my little baby is finally going out on his first date. Do you think you'll be alright?
Son: Mom, I'm fine, just leave me alone. I'm 18 and I'm not a little kid anymore.
Father: Honey, just cut the umbilical cord already and let him go!