Unlike her brother, who was a slacker and more into sports, Laura was very independent and focused with her education and was even distraught when her straight-A streak was broken by a mere B+.
In the season 3 episode, "Jailhouse Blues", after getting caught joyriding in a stolen car with his delinquent cousin, he attempted to sweet talk himself out of punishment, which only got him punished for the remainder of the year.
However, Urkel finds himself more considerate of other people after enduring being stalked by Myra and finding out what it's like being unwillingly pursued, although he would still continue clinging to Laura, both to be with her as well as to escape from Myra.