Illinois  |  Legal Ethics

Is somebody defined as a "client" when given legal advice and assistance by an attorney, even if the attorney's bills for providing that advice and assistance are paid by another person or organization? If, say, a husband uses an attorney frequently and pays all his/her bills - and his wife occasionally seeks entirely separate legal advice or help from the same attorney with regard to her own personal matters (regarding her will, say) which the attorney provides and bills the husband for - does the wife automatically also become a "client" of the attorney as well as the husband, even though she may not be paying attorney bills for the legal work being provided specifically for her? How is a "client" defined in these circumstances? Have these issues ever come up in Attorney Regulations or Court? Thanks in advance to anybody who can answer these questions!