Arnold's life is put on the line when the kids find out they cannot share a hospital room and end up running away on the night before Arnold's surgery.
Arnold wants to know where babies come from, but no one will give him a straight answer until one of the other tenants in the building, a woman whose pregnancy sparked Arnold's curiosity, complains to Mr. Drummond.
Arnold wants to meet his hero, world champion boxer Muhammad Ali. Willis and Kimberly meet him and say that their little brother is dying and that his last wish is to meet him.
Mr. Drummond's plans to officially adopt Arnold and Willis are delayed when a man claiming to be the boys' cousin claims he was promised custody in their father's will.
While Mr. Drummond's lawyers investigate Jethro Simpson's claim, Arnold and Willis prepare themselves for the possibility that they may have to live with the man.
Willis wants to beat an obnoxious braggart in an upcoming father and son athletic competition at the YMCA. Believing Mr. Drummond may not be able do it, he asks another man to be his "father".
Mr. Drummond is lonely so Arnold and Willis set him up with a date from a computer dating service but do not know that Mr. Drummond's friend set him up with a date as well.
Mr. Drummond scolds Arnold for secretly recording other people's conversations. Arnold disobeys him and records Kimberly's boyfriend Roger making racist comments about Willis to his sister.