Related Rule
United States of America
Practice Relating to Rule 105. Respect for Family Life
The US Field Manual (1956) reproduces Article 27 of the 1949 Geneva Convention IV. The manual also uses the same wording as Article 46 of the 1907 Hague Regulations. 
United States, Field Manual 27-10, The Law of Land Warfare, US Department of the Army, 18 July 1956, as modified by Change No. 1, 15 July 1976, §§ 266 and 380.
The US Air Force Pamphlet (1976) recalls that the 1949 Geneva Convention IV has provisions on the treatment of protected persons, including “to respect … family rights”. It also refers to Article 46 of the 1907 Hague Regulations, which provides for respect for “family honour”. 
United States, Air Force Pamphlet 110-31, International Law – The Conduct of Armed Conflict and Air Operations, US Department of the Air Force, 1976, §§ 14-4 and 14-6(a).
The US Soldier’s Manual (1984) instructs soldiers: “However different or unusual a foreign land may seem to you, remember to respect its people and their honor, family rights … and customs”. 
United States, Your Conduct in Combat under the Law of War, Publication No. FM 27-2, Headquarters Department of the Army, Washington, November 1984, p. 21.
According to the Report on US Practice, “Articles 4, 5 and 6 [of the 1977 Additional Protocol II] reflect general US policy on treatment of persons in the power of an adverse party in armed conflicts governed by common Article 3” of the 1949 Geneva Conventions. The report also notes: “It is the opinio juris of the US that persons detained in connection with an internal armed conflict are entitled to humane treatment as specified in Articles 4, 5 and 6 [of the 1977 Additional Protocol II].” 
Report on US Practice, 1997, Chapter 5.3.
The US Field Manual (1956) reproduces Article 26 of the 1949 Geneva Convention IV. 
United States, Field Manual 27-10, The Law of Land Warfare, US Department of the Army, 18 July 1956, as modified by Change No. 1, 15 July 1976, § 265.
The Annotated Supplement to the US Naval Handbook (1997) provides:
The United States supports the principles in [the 1977 Additional Protocol I], Article 74, that nations facilitate in every possible way the reunion of families dispersed as a result of armed conflict and encourage the work of humanitarian organizations engaged in this task. 
United States, Annotated Supplement to the Commander’s Handbook on the Law of Naval Operations, prepared by the Oceans Law and Policy Department, Center for Naval Warfare Studies, Naval War College, Newport, Rhode Island, November 1997, § 11.4, footnote 19.
In 1987, the Deputy Legal Adviser of the US Department of State affirmed: “We support the principle that … states facilitate in every possible way the reunion of families dispersed as a result of armed conflicts.” 
United States, Remarks of Michael J. Matheson, Deputy Legal Adviser, US Department of State, Sixth Annual American Red Cross-Washington College of Law Conference on International Humanitarian Law: A Workshop on Customary International Law and the 1977 Protocols Additional to the 1949 Geneva Conventions, American Journal of International Law and Policy, Vol. 2, 1987, p. 427.
According to the Report on US Practice, “Articles 4, 5 and 6 [of the 1977 Additional Protocol II] reflect general US policy on treatment of persons in the power of an adverse party in armed conflicts governed by common Article 3” of the 1949 Geneva Conventions. The report also notes: “It is the opinio juris of the US that persons detained in connection with an internal armed conflict are entitled to humane treatment as specified in Articles 4, 5 and 6 [of the 1977 Additional Protocol II].” 
Report on US Practice, 1997, Chapter 5.3.